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STUDIES  IN  CANCER  AND  ALLIED   SUBJECTS 


THE  STUDY 

OF 

EXPERIMENTAL  CANCER 

A  REVIEW 


STUDIES   IN   CANCER  AND  ALLIED   SUBJECTS 

Conducted  under  the  George  Crocker  Special  Research  Fund 
at  Columbia  University 

VOL.1.  T  H  E  S  T  UD  Y  O  F  E  XPERI  M  E  N  T  AL 
CANCER.       A  Review.      By  William   H.  Woglom,  M.D. 

Illustrated  with  many  plates.      In  two  bindings,  Quarto,  boards, 
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AND  DEVELOPMENT  OF  THE  SALIVARY 
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STUDIES  IN  CANCER 

AND    ALLIED    SUBJECTS 

THE    STUDY 

OF 

EXPERIMENTAL    CANCER 

A    REVIEW 

BY 

WILLIAM    H.  WOGLOM,   M.D. 

ASSISTANT   PROFESSOR,    COLUMBIA   UNIVERSITY,    ASSIGNED    TO    CANCER   RESEARCH 

SOMETIME   ASSISTANT   TO    THE   DIRECTOR   OF   THE   LABORATORIES   OF 

THE   IMPERIAL   CANCER   RESEARCH   FUND,    LONDON 

CONDUCTED  UNDER  THE  GEORGE  CROCKER  SPECIAL  RESEARCH 
FUND  AT  COLUMBIA  UNIVERSITY 

VOLUME    I 


COLUMBIA    UNIVERSITY    PRESS 

1913 

All  rights  reserved 


G.I 


Copyright,  1913, 
By   COLUMBIA  UNIVERSITY   PRESS. 


Set  up  and  electrotyped.     Published  August.  1913.     Reprinted  September,  191J. 


J.  S.  Gushing  Co.  —  Berwick  <fe  Smith  Co. 
Norwood,  Mass.,  U.S.A. 


TO   THE    MEMORY    OF   MY   FATHER 

WILLIAM    H.  WOGLOM 


PREFACE 

As  no  extensive  review  of  the  more  recent  experimental  investiga- 
tion of  cancer  was  available,  the  Advisory  Board  of  the  George 
Crocker  Special  Research  Fund  thought  it  wise  to  prepare  a  sum- 
mary. It  was  not  considered  advisable,  however,  to  attempt  a  critical 
precis  at  this  time,  since  much  of  the  work  is  so  new,  and  our  ideas 
regarding  the  disease  are  so  chaotic,  that  fair  criticism  and  evalua- 
tion are  well-nigh  impossible.  Nevertheless,  the  final  chapter  epito- 
mizes in  rough  outline  those  results  which,  in  all  likelihood,  will  prove 
to  be  permanent. 

Chemical  studies  have  been  omitted  because  a  number  of  excellent 
reviews  are  already  in  existence,  and  because  investigation  in  this 
field  has  thus  far  yielded  but  little  of  practical  importance,  while  the 
bacteriological  side  of  the  question  has  been  neglected  for  the  reason 
that  its  discussion  would  amount  to  little  more  than  a  list  of  micro- 
organisms. 

I  desire  to  express  my  obligation  to  Dr.  E.  F.  Bashford,  Director 
of  the  Laboratories  of  the  Imperial  Cancer  Research  Fund,  and  to 
his  colleagues,  Dr.  J.  A.  Murray  and  Dr.  B.  R.  G.  Russell ;  these 
gentlemen  have  read  the  book  in  manuscript  and  have  made  many 
valuable  suggestions.  The  assistance  of  Dr.  R.  M.  Rowe,  of  London, 
has  been  of  the  greatest  value,  while  to  Professor  F.  C.  Wood,  as  well 
as  to  Dean  Samuel  W.  Lambert,  I  am  much  indebted  for  continual 
advice  and  encouragement. 

All  the  illustrations,  with  the  exception  of  Fig.  6,  have  been  taken 
from  the  Scientilic  Reports  of  the  Imperial  Cancer  Research  Fund, 
with  the  courteous  permission  of  the  Executive  Committee  of  that 
Fund  and  of  the  Director,  Dr.  E.  F.  Bashford.  For  Fig.  6  I  am 
indebted  to  Dr.  Simon  Flexner,  editor  of  the  Journal  of  Experi- 
mental Medicine. 

WILLIAM    H.    WOGLOM. 

New  York,  July  i,  1913. 


CONTENTS 

CHAPTER  PAGE 

I.     Brief  Historical  Review i 

II.     Attempts  to  Produce  Tumors 20 

III.  Earlier  Observations  ox  the  Transmissibility  of  Cancer         .      39 

Transfer  from  one  person  to  another. 

(  Accidental. 

(  Experimental. 
Transplantation  of  tumors  into  their  bearers. 

(  Accidental. 

(  Experimental. 
Attempts  to  transfer  human  tumors  to  animals. 
Tumor  transplantation  within  the  same  species. 

IV.  The  Transplanted  Tumor 58 

The  stroma  reaction. 
Increase  of  virulence  or  adaptation  ? 
Stimulation  of  growth  power. 
Technic  of  inoculation. 

Relative  importance  of  soil  and  graft. 

Importance  of  uniform  dosage. 

Importance  of  uniform  soil. 

Inoculation  site. 

Interval  after  which  growth  becomes  apparent. 

Inoculation  of  stationary  or  receding  tumors. 

Transplantation  of  metastases. 

Inoculation  of  tumor  mixtures. 

Resistance  olTered  by  the  cancer  cell  to  various  agents. 
Comparative  growth  rate  of  the  malignant  cell. 
Fluctuations  in  growth  energy. 
Spontaneous  absorption. 

Histology  of  receding  tumors. 
Clinical  course  of  the  transplanted  tumor. 
Histological  variations  occurring  during  transplantation. 

In  the  parenchyma. 

In  the  stroma. 
Cultivation  of  cells  in  vitro. 


CONTENTS 


V.  Resistance 128 

Natural  resistance. 

Influence  of  age. 
Influence  of  race. 
Influence  of  health. 
Influence  of  sex. 
Influence  of  pregnancy. 
Acquired  resistance,  active  and  passive. 

Active  resistance  evolved  by  tumor. 
Pan-immuaity. 

Active  resistance  probably  evolved  only  by  intact 
tumor  cells  of  same  species. 
Active  resistance  evolved  by  normal  tissue. 

Active  resistance  probably  evolved  only  by  intact 

normal  cells  of  same  species. 
No  active  resistance  with  autologous  tissue. 
Can  tumor-bearing  animals  be  made  actively  resistant  ? 
Premetastatic  stage  of  active  resistance. 
Distribution  of  active  resistance. 
First  appearance  and  duration  of  active  resistance. 
Passive  resistance. 
Are  natural  and  acquired  resistance  transmissible  by  heredity  ? 
Nature  of  the  resistant  state. 

VI.  Hypersusceptibility 178 

Anaphylaxis 

VIL    The  Spontaneous  Tumor 183 

Frequency  of  tumors  among  the  lower  animals. 
Structure  of  origin  in  the  mouse. 
The  question  of  malignancy. 

Occurrence  of  metastases. 

Infiltrative  growth. 

Altmann's  granules. 
Etiology. 

Influence  of  infectivity. 

Influence  of  age  and  sex. 

Influence  of  lactation. 

Influence  of  heredity. 

Influence  of  inflammation. 

Etiology  theoretically  considered. 
Histology. 
Clinical  course. 
Relation  between  tumor  and  host. 


CONTENTS  XI 

CHAPTER  PAGE 

VIII.    Tumors  of  a  Nature  still  Undecided 227 

Lympho-sarcoma  of  the  dog. 
Thyroid  adeno-carcinoma  of  the  trout. 
Transmissible  sarcoma  of  the  fowl. 

IX.     Therapeutics 256 

X.     General  Summary 270 

Index  of  Authors 275 

Index  of  Subjects 283 


CHAPTER  I 
BRIEF   HISTORICAL   REVIEW 

From  the  earliest  days  in  the  history  of  medicine,  when  cancer  had 
aheady  been  identified  to  some  extent  as  an  incurable  and  fatal 
disease,  conjecture  regarding  its  nature  and  cure  has  been  incessant, 
and  theories  almost  without  number  have  been  advanced  to  explain 
its  origin. 

Speculation  has  been  traced  back  to  the  Eg>TDtians,  who  were  ac- 
quainted with  cancer  as  early  as  1500  B.C.,  although,  according  to 
Joachim,^  they  included  the  most  various  swellings  as  part  and  parcel 
of  the  disease.  But  the  lesion  which  we  now  recognize  as  cancer  was 
probably  not  unknown  to  them,  for  they  described  an  ulcerating 
disease  and  treated  it  with  an  arsenic  salve. ^,  It  was  certainly  familiar, 
at  any  rate,  to  the  Egyptians  of  a  somewhat  later  period,  for  manu- 
scripts prepared  about  800  B.C.  contain  descriptions  of  cancer  of  the 
breast„^  which  leave  no  doubt  that  the  disease  was  recognized  at  that 
time ;  even  before  the  dates  just  quoted,  however,  cancer  was  being 
extirpated  in  India,  and  a  salve  applied  to  the  wound  in  the  hope  of 
preventing  recurrence  of  the  disorder.^ 

With  cancer  of  the  breast  Hippocrates  was  fairly  well  acquainted 
and  he  recognized  the  occurrence  of  malignant  disease  in  certain  of 
the  internal  organs  as  well.  He  believed  it  to  be  due,  in  common 
with  all  other  pathological  conditions,  to  a  deficiency  or  an  excess  of 
bile,  blood,  or  mucus. 

Before  the  day  of  the  Roman  physician  Celsus,  the  term  carcinoma 
included  the  most  bizarre  collection  of  swellings.  Celsus,*"  however, 
distinguished  cancer  from  carcinoma,  including  under  the  former  head- 
ing many  lesions  which  are  now  recognized  as  simply  inflammatory. 

1  Die  Lehre  von  der  Krebskrankheit,  etc.,  Wolff,  Jena,  1907,  Teil  I,  3. 

2  Arndt,  cited  by  Wolff,  3.  ^  Oefele,  cited  by  Wolff,  3. 
4  Wolfler,  cited  by  Wolff,  3.                          ^  Wolff,  7. 

I 


2  BRIEF    HISTORICAL    REVIEW 

He  not  only  separated  several  of  the  benign  neoplasms  (among  them 
ganglion  and  lipoma)  from  the  maHgnant  growths,  but  described  the 
enlargement  of  the  axillar}-  l}Tnph  nodes  accompanying  cancer  of  the 
breast,  and  seemed  to  be  familiar  with  carcinoma  of  the  Hver  and 
spleen.  Nor  was  he  unaware  of  the  serious  nature  of  cancer,  for 
he  expressed  the  opinion  that  it  could  be  cured  only  in  the  first,  or 
indurative  stage,  counseled  ablation  of  the  less  maHgnant  growths, 
devised  operative  measures  for  removal  of  carcinoma  of  the  Hp,  and 
extirpated  cancer  of  the  breast. 

Galen, ^  who  in  the  second  century-  elaborated  the  theories  of  Hippoc- 
rates, recognized  with  his  predecessor  four  cardinal  fluids  upon  whose 
proportion  to  one  another  depended  the  state  of  the  body.  These 
fluids  were  blood,  mucus,  yellow  bile  (derived  from  the  liver),  and  black 
bile  fsecreted  by  the  spleen) ;  to  the  collection  in  undue  amount  of  the 
material  last  mentioned  he  ascribed  the  origin  of  malignant  growths. 
If  the  bile  were  sharp  and  irritating,  there  arose  an  ulcerating  cancer ; 
if  mild,  one  of  the  non-ulcerating  t}'pe.  The  spread  of  the  disease  was 
well  known  to  Galen,  but.  ignorant  of  the  existence  of  the  lymphatics, 
he  beheved  that  it  took  place  by  way  of  the  veins.  His  therapeutic 
endeavors  were  directed  particularly  toward  attaining  a  diet  which 
should  not  contain  any  of  the  substances  productive  of  black  bile, 
while  purging  played  no  unimportant  part  in  the  treatment.  Con- 
sidering both  procedures  of  the  highest  utility,  he  nevertheless 
did  not  entirely  neglect  surgical  inter^-ention,  which  he  conceived, 
however,  to  be  of  secondar}'  value  only,  reasoning  that  it  was  illogical 
to  treat  a  constitutional  disease  by  measures  so  purely  local  as  surgery. 

Leonides  -  was  the  first  investigator  wdth  courage  requisite  to  dis- 
card the  advice  of  Hippocrates,  never  to  operate  on  an  ulcerating 
cancer.  He  practised  with  the  knife  and  cautery  the  most  thorough 
and  energetic  treatment  of  carcinoma  of  the  breast,  and  was  the  first 
to  appreciate  the  importance  of  retraction  of  the  nipple  as  a  diagnos- 
tic sign. 

From  the  time  of  Leonides,  about  i8o  B.C.,  until  the  Renaissance, 
the  art  of  the  physician  progressed  only  to  a  small  degree,  if,  indeed,  it 
advanced  at  all ;  but  -^dth  the  awakened  interest  in  art,  Hterature,  and 
science  which  made  this  such  an  eventful  period,  there  was  aroused  a 

1  Wolff,  lO.  2  Wolff,  14. 


BRIEF    HISTORICAL   REVIEW  3 

renewed  attention  to  medicine.  Vesalius  ^  exposed  several  of  the 
errors  of  Galen  and  his  predecessors,  while  his  pupil  Fallopius  ^  made 
important  contributions  toward  the  diagnosis  of  cancer ;  and  although 
he  preferred  to  treat  the  disease  with  arsenic,  his  contemporary, 
Ambroise  Pare,^  was  fully  ahve  to  the  necessity  of  total  ablation 
whenever  its  performance  was  possible. 

Throughout  more  than  a  thousand  years  Galen's  hypothesis  of  the 
four  humors  had  ruled  supreme  in  the  domain  of  medicine,  without 
an  attempt  having  been  made  to  depose  it.  With  Paracelsus,"* 
however,  there  appeared  signs  of  an  imwilHngness  to  accept  it  in 
its  entirety,  and  in  the  next  century  the  final  overthrow  was  ac- 
complished through  the  simultaneous  operation  of  several  factors, 
the  most  important  of  which  were  the  demonstration  of  the  circula- 
tion of  the  blood,  and  the  revelation  of  the  red  blood  cells  and  lymph 
channels. 

With  these  discoveries,  and  that  of  the  cellular  structure  of  cork  by 
Hooke,  hypothesis  had  begun  to  give  place  to  observation,  and  follow- 
ing the  improvement  of  the  microscope  came  the  description  of  the 
nucleus  by  Brown. '^  However,  the  cells  of  Hooke  and  his  immediate 
successors  were  but  chambers  in  the  plant  tissue,  while  it  is  doubtful 
from  Brown's  description  whether  he  recognized  the  importance  of  his 
observation.  It  remained  for  Schleiden  ^  to  appreciate  the  significance 
of  the  cell  as  a  unit  in  the  organism  of  the  plant,  and  for  Schwann^ 
to  apply  this  conception  to  the  animal  tissues.  This  new  work  en- 
hanced greatly  the  significance  of  Miiller's  ^  earlier  announcement  of 
the  cellular  structure  of  certain  growths,  and  encouraged  him  to 
reexamine  tumors  in  which  no  cells  had  at  first  been  found,  as  a  result 
of  which  he  ^  was  enabled,  with  lenses  of  higher  power,  to-  perceive  a 
cellular  structure  also  in  these. 

But  even  after  the  cell  had  been  accepted  as  the  tissue  unit,  specula- 

iWolfE,  32.  2  Wolff,  34. 

3  Wolff,  42.  nvolff,  51. 

^  Observations  on  the  Organs  and  Mode  of  Fecundation  in  Orchideoe,  etc.,  London,  1831. 
^Arch.f.  Anat.,  Physiol.,  etc.,  (Miiller),  1838,  137. 

^  Mikroskop.  Untersiichimgen  iiher  die  U ebereinstimmimg  in  der  Struktiir  u.  dem  Wachstum 
der  Thiere  u.  Pflanzen,  Berlin,  1839. 

^  Arch.  f.  Anat.,  Physiol.,  etc.,  (Miiller),  1836,  p.  ccxviii. 

®  Ueher  denfeineren  Bau  und  die  Formen  der  krankhaften  Geschwillste,  Berlin,  1838. 


4  BRIEF    HISTORICAL    RZ\1EW 

tion  regarding  its  actual  source  continued  rife,  and  the  relation  of  the 
intercellular  substance  to  cell  genesis  became  the  subject  of  much 
debate.  Believed  by  Schwann  to  be  destined  for  transformation  into 
new  cells,  its  insignihcance  in  this  process  was  first  appreciated  by 
Remak.-  A  series  of  publications  begun  in  1S41  culminated  in  a 
description  -  of  cell  division  in  which  it  was  denied  that  the  inter- 
cellular substance  was  able  to  produce  new  cells,  and  declared  to  be 
very  probable  that  all  animal  cells  were  created  through  the  progres- 
sive diidsion  of  preexisting  cells. 

According  to  Virchow"s  conception.'^  it  was  just  as  impossible  for  a 
non-cellular  material  to  elaborate  a  cell  as  it  was  for  the  decomposition 
products  of  animal  or  vegetable  matter  to  give  origin  to  an  infusorian. 
Omnis  cellida  e  cellula.  as  animals  were  derived  only  from  animals,  or 
plants  from  plants. 

The  cells  of  a  tissue  '  which  was  to  become  the  seat  of  a  tumor  began 
to  swdl  and  divide,  possibly  as  a  result  of  irritation.  If  di^-ision 
went  on  rapidly,  and  if  the  members  of  successive  generations  became 
progressively  smaller,  the  tissue  arrived  finally  at  the  granulation 
stage  in  which,  like  granulation  tissue,  it  was  indifferent  in  appear- 
ance, the  concUtion  being  analogous  to  that  obtaining  in  the  embryo 
in  the  early  days  foUo^dng  fertilization.  Upon  this  state  there  super- 
A'ened  one  of  differentiation,  leading  to  the  ffnal  stage  in  which  the 
tumor  assumed  its  finished  form. 

The  growth  of  a  mali^gnant  tum^or  took  place,  not  by  increase 
of  its  elements,  but  by  the  fusion  of  accessory  foci  evolved  in  its 
neighborhood,  a  method  of  dissemination  which  proved  that  the 
primar}'  nodule  exercised  a  certain  stimulation  upon  the  surrounding 
parts  through  the  agency  of  a  secreted  fluid.  The  process  was  ex- 
actly the  same  in  metastatic  tumors,  but  whether  only  a  fluid  excre- 
tion were  concerned  in  this  case  was  a  question  difficult  of  decision. 
It  was  not  at  all  improbable  that  in  some  instances  ceUs  were 
actuall}'  transported,  to  act  as  the  infective  material;  and  although 

^  Untersuchungen  iiber  die  Eiitwkklung  der  Wirbelthiere.  Berlin,  1855. 
^Arck.f.  Anat.,  Physiol.,  etc.,  Qliiller),  1852,  47. 
^  Arch.  f.  path.  Anat.,  etc.,  (Virchow),  1855,  via,  3. 
Die  Cellidarpathologie,  4te  Aufl.,  Berlin,  1871,  24. 
*  Die  krankhaften  Gesckwiilste,  Berlin,  1863,  89. 


BRIEF    HISTORICAL   REVIEW  5 

this  was  not  a  common  occurrence,  still,  as  the  cells  within  the 
tumor  produced  the  injurious  fluid  it  was  not  imreasonable  to 
imagine  them  able  to  carry  it  to  other  locaHties.  It  was  certain, 
however,  that  metastases  were  not  a  result  of  proHferation  of  the 
transported  cells,  but  rather  the  product  of  healthy  elements  in  the 
neighborhood,  incited  to  mahgnant  growth  by  the  excretions  of  cancer 
cells  deposited  there. 

The  vahdity  of  Virchow's  h}pothesis  was  seriously  affected  by  the 
later  work  of  Thiersch,^  who  advanced  proof  that  the  cells  of  epitheho- 
mata  developed  only  from  epithehum  —  never  from  connective  tissue. 
And  even  though  the  examination  of  serial  sections  failed  to  demon- 
strate in  every  case  an  actual  connection  between  the  tumor  and  the 
epithehum,  it  was  not  unreasonable  to  postulate  a  pre^'ious  association 
with  this  tissue,  since  it  might  have  been  present  in  the  form  of  cell 
islands  which  had  become  estranged  from  their  surroundings  during 
the  development  of  the  embryo.  In  Thiersch's  opinion,  metastases 
in  the  l^miph  nodes  were  to  be  ascribed  with  much  more  reason  to  the 
actual  proHferation  of  transported  tumor  cells  than  to  growth  of  the 
normal  elements  of  the  node  under  stress  of  stimulation  by  the  h}^o- 
thetical  growth-exciting  fluid.  Furthermore,  Waldeyer,-  amphfying 
the  investigations  of  Thiersch,  demonstrated  that  all  carcinomata  were 
of  epithehal  origin  and  denied  that  a  transformation  of  connective 
tissue  elements  into  cancer  ceUs  ever  occurred.  He  agreed  with 
Thiersch  that  metastases  were  the  product  of  proHferation  on  the  part 
of  transported  cells  and  attributed  a  large  share  in  the  production 
of  secondary  deposits  to  the  ameboid  motion  which,  in  conjunction 
with  Carmalt,^  he  had  demonstrated  in  the  cancer  cell.  To  this 
point  Lambert  and  Hanes  ^  have  again  called  attention  •  within  the 
past  few  years. 

Thus  was  overthrown  the  first  half  of  Virchow's  h}'pothesis.  The 
remainder,  which  sought  partially  to  explain  by  irritation  the  launch- 
ing of  ceUs  upon  a  career  of  lawless  growth,  is  stiU  intact,  and  accepted 

•    ^  Der  Epithelialkrehs ,  namentlich  der  Haiit,  Leipzig,  1865,  58. 
^  Arch.  f.  path.  Anat.,  etc.,  (Virchow),  1867,  xli,  470. 
^Arch.f.  path.  Anat.,  etc.,  (Virchow),  1872,  Iv,  481. 
^  Jour.  American  Med.  Assoc,  1911,  Ivi,  791. 
Arch.f.  path.  Anat.,  etc.,  (Virchow),  1912,  ccix,  12. 


6  BRIEF    HISTORICAL   REVIEW 

by  many  investigators  of  the  present  day  as  an  explanation,  in  part  at 
least,  of  the  inception  of  mahgnant  proliferation.  The  occurrence  of 
cancer  of  the  mouth  in  smokers,  of  carcinoma  of  the  stomach  upon  the 
ground  of  a  gastric  ulcer,  of  cancer  of  the  gall-bladder  in  connection 
with  cholelithiasis,  and  many  other  instances  of  an  apparent  relation 
between  chronic  irritation  and  mahgnant  growth  have  been  cited  time 
and  again  in  favor  of  this  conception.  To  mention  specifically  but  a 
few  observers.  Neve  ^  has  directed  attention  to  the  natives  of  Kashmir 
who  wear  underneath  the  clothing  a  basket  of  glowing  charcoal,  and 
in  whom  epithelioma  is  very  common  upon  the  anterior  abdominal 
wall  at  the  site  where  the  basket  is  carried,  while  carcinoma  of  the 
mouth  is,  according  to  the  experience  of  Chalmers  and  Perr}^^  very 
frequent  among  the  women  of  India  who  chew  the  betel-nut  and  retain 
it  in  the  mouth  during  sleep.  Nor  are  instances  wanting  among  the 
lower  animals.  Bashford  ^  has  cited  the  observations  of  Captain 
Brodie-Mills  upon  the  great  frequency  of  squamous  cell  carcinoma  at 
the  root  of  the  right  horn  among  the  cattle  used  in  India  for  draught 
purposes  —  the  right  horn  being  used  by  the  natives  for  the  attach- 
ment of  agricultural  implements  or  wagons.  PUcque"^  noticed  that 
carcinoma  in  horses  was  commonly  found  where  the  bit  irritated  the 
corners  of  the  mouth,  and  subcutaneous  fibromata  ahnost  invariably 
at  the  point  of  pressure  by  coUars  or  girths,  while  in  dogs  the  most 
posterior  mamm^,  those  most  often  engorged,  were  the  ones  more 
frequently  affected  by  cancer.  In  cats,  the  upper  hp,  which  was  the 
one  more  hkely  to  be  wounded,  was  the  site  of  election  for  mahgnant 
disease. 

Thiersch  ^  ascribed  the  development  of  epithehoma  to  a  disturbance 
in  the  equihbrium  between  epithelium  and  connective  tissue  brought 
about  by  senile  atrophy  of  the  latter,  while  the  pioHferative  or 
bioplastic  energy  of  the  epithehum  remained  at  the  same  time  unim- 
paired. Mahgnant  growth  thus  occurred  not  by  reason  of  an  in- 
crease in  the  ofi'ensive  power  of  epithelium,  but  through  a  decrease 

1  British  Med.  Jour.,  1910,  ii,  589. 

2  Cited  by  Bashford,  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  190S, 
19. 

^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  22. 

*  Revue  de  Chir.,  1889,  ix,  521. 

^  Der  Epithelialkrebs,  namentlich  der  Haiit,  Leipzig,  1865,  78. 


BRIEF   HISTORICAL    REVIEW  7 

in  the  defenses  of  the  connective  tissue.  Chronic  irritation,  inflamma- 
tion, or  trauma  might  under  certain  conditions  act  as  the  final 
stimulus  and  thus  be  an  indirect  cause  of  mahgnant  growth. 

Waldeyer,^  on  the  contrary,  urged  an  opposite  conception :  That 
with  increasing  age  epithelial  structures  lost  their  vigor  and  became 
surrounded  by  a  replacement  fibrosis,  the  result  of  an  increased  activity 
on  the  side  of  the  connective  tissue.  The  isolation  of  epithelial  ele- 
ments might  be  attended  by  any  one  of  three  possible  results ;  most 
frequently  such  cells  underwent  necrosis,  at  other  times  there  super- 
vened cyst  formation,  while  in  the  third  place  they  might  assume 
malignant  growth.  An  important  prelude  to  this  type  of  prolifera- 
tion was  the  appearance  of  changes  in  the  connective  tissue  extraor- 
dinarily Hke  those  accompanying  inflammation. 

Hauser,-  although  admitting  that  epithelium  was  the  most  vigorous 
of  all  the  tissues,  maintained  that  Thiersch's  hypothesis  did  not 
explain  the  enormous  increase  in  growth  energy  so  frequently  encoun- 
tered in  cancers  of  the  cylindrical  cell  type.  This  phenomenon  was 
but  insufficiently  explained  by  the  assumption  of  a  decrease  in  the 
physiological  defenses,  and  there  was  required  the  addition  of  a  posi- 
tive quantity  to  the  opposite  side  of  the  equation,  which  might  well 
be  an  augmentation  in  the  assimilative  power  of  the  epithelium  coupled, 
perhaps,  with  an  increased  avidity  for  food-stuffs.  Furthermore,  if 
the  h3q3othesis  were  correct,  one  would  anticipate  the  more  frequent 
occurrence  of  multiple  cancers,  whereas  the  disease  was  almost  without 
exception  local  in  origin  and  limited  to  a  single  organ,  if  not  to  one  part 
of  that  organ.  Finally,  connective  tissue  was  often  not  so  passive  as 
the  hypothesis  assumed,  for  in  many  scirrhous  carcinomata  growth  of 
the  stroma  proceeded  with  the  greatest  vigor  and  occasionally  out- 
stripped even  the  epithehal  proliferation. 

v.  Hansemann  ^  criticized  Thiersch's  hypothesis  on  the  ground  that 
it  explained  neither  the  relatively  uncommon  occurrence  of  carcinoma, 
nor  its  presence  in  the  young,  and  extended  the  latter  objection  to 
include  the  fact  that  carcinoma  in  early  life  was  exceptionally  malig- 
nant.    Were  the  conception  correct,  the  case  should  be  reversed. 

^  Arch.  f.  path.  Anal.,  etc.,  (Virchow),  1867,  xli,  470;    1872,  Iv,  67. 

^  Das  Cylindercpithel-carcinom  des  Magens  wid  des  Dickdarms,  Jena,  1890,  135. 

^  Die  mikroskopische  Diagnose  der  hosartigen  Geschwiilste,  Berlin,  1902,  215. 


8  BRIEF    HISTORICAL   REVIEW 

Although  Cohnheim  ^  was  not  the  first  to  suggest  a  connection  be- 
tween mahgnant  growths  and  embryonic  rests,  it  is  with  his  name  that 
the  hypothesis  is  generally  associated.  Having  described  a  congenital 
myo-sarcoma  of  the  kidney,  he  suggested  that  the  tumor  might  have 
originated  from  germinal  muscle  cells  which  had  been  snared  off  at  a 
time  when  the  foundations  of  the  urinary  organs  were  being  laid  down. 
He  assumed  that  in  early  embryonal  hfe  more  cells  than  requisite  were 
produced  and  that  the  unutiHzed  elements,  with  all  their  inherent  power 
of  proHferation,  were  cut  oft"  at  a  very  early  period,  probably  corre- 
sponding to  the  interval  between  differentiation  of  the  germinal  layers 
and  completion  of  the  foundations  for  the  various  organs. 

Cohnheim  sought  support  for  his  suggestions  in  the  undift'erentiated 
embryonal  appearance  of  tumor  cells  as  well  as  in  the  congenital  or 
early  postnatal  occurrence  of  neoplasms,  although  admitting  that  it 
would  go  hard  with  his  hypothesis  were  it  forced  to  depend  upon  the 
latter  alone  for  substantiation.  Still,  the  conception  did  not  in  the  least 
require  that  the  tumor  itself  should  be  congenital,  but  merely  the 
foundation  for  it.  What  were  the  circumstances  able  to  initiate  growth 
in  embryonic  rests  he  made  no  definite  effort  to  estabhsh,  although 
offering  the  suggestion  that  one  of  them  might  be  repeated  arterial 
congestion  or  even  inflammatory  hyperemia,  so  that  the  idea  of 
traumatic  etiology  inight  be  true  wdthin  limitations.  It  was  impos- 
sible, however,  to  apprehend  the  influence  which  excited  or  released 
the  power  of  indefinite  proHferation,  for  it  had  not  yet  been  learned 
in  what  manner  growth  was  normally  inhibited.  It  might  be  that 
normal  tissues  were  able  to  exert  a  certain  control  over  the  germinal 
displacements  and  thus  keep  them  from  proHf crating,  while  trauma 
might  so  weaken  this  physiological  restraint  in  the  neighborhood  of 
a  cell  rest  as  to  permit  the  inception  of  growth.  Cohnheim  believed 
that  his  explanation  accounted  for  the  variety  of  tissues  so  often  found 
in  tumors,  as  well  as  for  the  occurrence  of  certain  neoplasms  in  specific 
localities.  It  was  a  clinical  observation  of  many  years'  standing  that 
epithehal  growths  were  common  at  the  various  orifices  of  the  body,  and, 
indeed,  this  fact  had  been  made  use  of  by  Virchow  to  sustain  the  hy- 
pothesis of  mechanical  insult.     But  if  injury  were  the  factor  determin- 

^  Arch.  f.  path.  Anat.,  etc.,  (Virchow),  1875,  Ixv,  64. 
Vorlesungen  iiber  dig.  Path.,  Bd.  i,  Berlin,  1877,  634. 


BRIEF    HISTORICAL   REVIEW  9 

ing  continuous  proliferation  it  was  hard  to  understand  why  tumors 
should  be  so  rarely  met  with  on  the  hands  and  feet,  which  of  all  parts 
of  the  body  were  most  eminently  exposed  to  trauma.  An  elucidation 
of  the  frequent  occurrence  of  epithelial  growths  at  certain  sites  must, 
therefore,  be  sought  elsewhere,  and  most  reasonably  in  the  fact  that 
at  the  apertures  of  the  body  there  was  a  comphcation  in  the  embryonal 
structure  at  one  or  another  stage  of  development. 

R.  Hertwig  ^  thought  that  a  hypothesis  which  would  refer  the  origin 
of  neoplasms  to  embryonal  rests  was  irreconcilable  with  the  fact  that 
tumors,  and  particularly  mahgnant  tumors,  were  more  frequent 
in  the  higher  age  periods.  It  must  be  assumed  that  the  body  was 
everywhere  provided  with  nutritive  materials  which  were  only  await- 
ing utilization.  How  was  it,  then,  that  for  decades  the  colonies  of 
embryonal  cells  did  not  make  use  of  this  material?  Either  they  were 
unable  to  do  so  (for  lack  of  the  very  power  which  Cohnheim's  concep- 
tion emphasized  and  upon  which  it  was  built),  or  they  were  by  some 
means  excluded  from  sharing  the  universal  food-stuff  —  a  supposi- 
tion which  was  inconceivable.  Furthermore,  Hertwig  did  not  beHeve 
that  a  comparison  could  be  instituted  between  embryonal  and  tumor 
cells  on  a  common  ground  of  absence  of  differentiation.  Those  of 
the  embryo  were  undifferentiated,  it  was  true,  but  they  possessed 
an  increasing  tendency  to  differentiate,  or,  in  other  words,  to  exchange 
cytotypic  for  organotypic  growth,  while  the  slight  disposition  originally 
present  in  the  elements  of  a  tumor  became  progressively  weaker  and 
weaker. 

The  problem  of  malignant  growth,  according  to  Hertwig,  was  a 
double  one,  since  it  must  first  be  explained  how,  in  an  organism  which 
had  reached  its  Hmit  of  size,  the  cells  normally  lost  their  autonomous 
growth  and  subjected  themselves  to  their  surroundings,  and  secondly 
it  must  be  ascertained  what  changes  had  to  occur  in  cells  in  order 
that  they  might  escape  from  the  control  exercised  over  them  by  the 
organism. 

Cohnheim's  hypothesis  has  been  criticized  by  Bashford  ^  in  a  dis- 
cussion of  cancer  in  the  cheek  and  abdominal   wall  which,   almost 

1  Festschrift  Ernst  Haeckel,  Jena,  1904,  347. 

^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  24,  and  Introduction, 
p.  ix. 


10  BRIEF    HISTORICAL    REVIEW 

unknown  in  Europeans,  occurs  ^^•ith  great  frequency  among  the 
natives  of  India  follo-^ing  chronic  irritation  produced  by  the  use  of  the 
betel-nut  or  Kangri  basket.  '".  .  .  it  becomes  necessary  to  postulate 
further  a  uniform  and  abundant  distribution  of  "  embryonic  rests '  over 
the  body,  or  to  assume  a  different  distribution  of  "embryonic  rests"  in 
Europeans  and  native  races,  coinciding  with  the  points  they  respec- 
tivelv  select  for  the  indulgence  of  various  practices  invohdng  the  appli- 
cation of  peculiar  irritations.""  And  further:  '' Suffice  it  to  sa}^  that 
if  all  forms  of  cancer  are  to  be  explained  by  such  speculations  and  the 
interA'ention  of  congenital  'germs"  is  to  hold  good  for  all  cases,  then  it 
must  be  assumed  that  such  germs  are  as  uniformly  distributed,  e.g. 
over  the  surface  of  the  body  of  all  vertebrates  as  the  skin  is  itseh.  and 
thus  the  explanation  becomes  no  explanation  at  aU." 

While,  in  the  opinion  of  Ribbert.^  many  carcinomata  almost  cer- 
tainlv  took  their  origin  from  embryonal  cell  rests,  it  was  evident  that 
such  structures  were  not  invariably  able  to  assume  the  malignant 
tvpe  of  growth,  since  many  of  them  lay  indefinitely  quiescent. 
.\lthough  they  possessed,  in  common  with  other  epithehal  cell  groups, 
the  normal  tendency  to  penetrate  underhing  connective  tissue,  this 
latter  must,  under  ordinary  conditions,  exert  some  sort  of  inhibitory 
influence  preventing  invasion  on  the  part  of  the  epithehum.  and  not 
until  this  opposition  had  been  removed  could  the  potential  energies 
of  the  epithelium  be  unfolded.  The  release  of  the  normal  invasive 
faculty  was  brought  about  through  the  presence  in  the  connective 
tissue  of  simple  hyperemia,  or  of  inflammatorv'  lesions  such  as  round 
cell  infiltration,  or  proliferation  of  the  fixed  elements  with  a  con- 
comitant production  of  blood  vessels,  an  analogous  situation  occur- 
ring in  the  development  of  glandular  structures  in  the  embryo,  where 
downgrowth  of  epithelium  was  always  preceded  by  alterations  in  the 
subjacent  tissue.  Xevertheless.  in  the  fully  developed  organism  at 
least,  cellular  changes  in  the  connective  tissue  did  not  invariably 
ehcit  epithehal  invasion,  for  inflammation,  even  though  it  continued 
over  an  extended  period  of  time,  was  not  always  followed  by  the 
development  of  carcinoma.     Hence,  the  inflammatory  lesions  which 

"^  Arch.  f.  path.  Anat.,  etc.,  rvircliovrj.  1894,  cxxx\-,  433. 
Geschu'idstlehre,  Bonn,  1904,  552. 
Das  Karzinom  des  Menschen,  Bonn,  1911,  482. 


BRIEF    HISTORICAL   REVIEW  II 

had  been  found  to  precede  carcinoma  must  be  distinguished  by  some 
special  characteristic,  and  the  whole  process  could  best  be  explained 
on  the  assumption  that  they  were  the  product  of  certain  agents  elab- 
orated by  the  epithelium  itself  —  that  the  epithelial  cells  prepared  the 
soil  into  which  they  were  later  to  penetrate.  Such  a  chain  of  events, 
however,  might  result  merely  in  the  occurrence  of  heterotopia,  and  to 
explain  actual  malignancy  it  was  necessary  to  postulate  in  addition 
that  the  epitheHal  cells  suffered  a  loss  in  differentiation,^  through 
which  they  became  enabled  to  proliferate  more  luxuriantly.  In  the 
case  of  embryonal  rests,  malignant  growth  was  the  more  readily  initi- 
ated because  the  cells  had  not  yet  undergone  complete  differentiation, 
and  were  therefore  more  ready  to  start  upon  a  career  of  indefinite 
multipHcation. 

Ribbert's  work  was  the  anatomical  expression  of  a  biological  law 
formulated  by  Weigert,^  who  had  suggested  that  as  tumors,  either 
benign  or  malignant,  developed  without  the  interference  of  external 
stimuH  or  after  the  action  of  those  which,  under  other  circumstances, 
did  not  give  rise  to  tumors,  stimulus  could  be  considered  merely  as 
an  accessory  cause.  Such  an  etiological  factor  could  only  arouse  a 
latent  disposition  toward  the  growth  of  a  tumor  or  accelerate  the 
proliferation  of  one  already  present.  To  explain  this  disposition,  it 
might  be  imagined  that  there  was  a  misrelation  between  the  proHf-. 
erative  energies  of  some  region  of  the  organism  and  its  neighboring 
tissues,  which  had  occurred  either  through  increased  growth  activity 
on  the  part  of  certain  cells  or  through  decreased  resistance  of  those 
tissues  determining  the  bounds  of  physiological  growth.  The  for- 
mer might  take  place  in  the  way  that  Cohnheim  had  postulated,  or 
else  single  cell  groups  might  retain  their  growth  energy  after  the 
embryonal  period  had  passed.  A  decreased  resistance,  on  the  other 
hand,  might  be  congenital  for  one  or  another  locahty  or  develop  in 
later  life  by  the  more  rapid  aging  of  certain  tissues  —  a  conception 
which  had  been  advanced  by  Thiersch  and  with  which  Weigert 
expressed  his  agreement.  For  neither  non-maUgnant  nor  malignant 
proliferation,  however,  was  it  necessary  to  assume  the  application 

^  Ribbert  distinguished  very  sharply  between  such  a  condition,  and  one  of  specific 
cancerous  degeneration. 

2  Ueher  Entziindiing,  Eulenburg's  Real-Encyclopddie  der  gesammten  Heilkunde,  erste 
Aufl.,  1880,  iv,  644;  zweite,  1886,  vi,  325. 


12  BRIEF    HISTORICAL    REVIEW 

from  without  of  a  direct  stimulus  to  cell  growth,  for  in  both  cases  there 
were  concerned  only  those  proclivities  toward  continuous  multipli- 
cation which  had  been  inherent  in  the  cells  since  the  embryonic  period. 

Hauser/  in  a  series  of  articles  in  which,  to  support  his  contention, 
reference  was  made  to  his  own  previous  observations,^  denied  strenu- 
ously the  correctness  of  the  view  held  by  Ribbert  regarding  the  develop- 
ment of  carcinoma.  This  disorder,  in  his  opinion,  could  be  produced 
only  through  a  fundamental  change  in  the  biological  properties  of  the 
implicated  cells,  and  with  the  assumption  of  such  a  change  certain 
morphological  data  were  in  entire  accord.  The  loss  of  physiological 
function,  the  increase  in  the  size  of  the  cell  and  its  nucleus,  the  higher 
chromatin  content  of  the  latter,  the  presence  of  abnormal  mitotic 
figures,  and  finally,  the  enormous  capacity  for  multiplication  —  all 
indicated  an  entirely  new  type  of  cell.  The  process  was,  in  short,  a 
specific  cancerous  degeneration,  and  a  weakening  of  the  defenses  set 
up  by  the  connective  tissue  against  epithelium  could  play  but  a  sub- 
ordinate role  in  the  process.  While  Ribbert  had  always  contended 
that  a  new  growth  increased  simply  by  the  multiplication  of  its  own 
cells  —  ans  sich  heraus  —  Hauser,  on  the  contrary,  maintained  that  it 
spread  by  a  wave  of  cancerous  degeneration  which  successively  attacked 
normal  structures  at  its  margin. 

In  this  connection  the  views  of  Adami  ^  are  of  interest.  He  de- 
scribed an  early  multiple  tumor  of  the  adrenal  cortex  "  .  .  .  in  which 
occasional  cells  in  the  immediate  neighborhood  of  the  small  mass  of 
new  growth,  while  still  retaining  their  relationship  to  the  columns  of 
the  zona  radiata,  by  their  enlarged  and  deep-staining  nuclei  stood  out 
as  of  the  can£erous_t^pe.''  He  quoted,  furthermore,  certain  observa- 
tions of  Horst  Oertel  upon  the  apparently  direct  cancerous  transfor- 
mation of  liver  cells  in  a  case  of  multiple  hepatic  carcinoma,  and 
concluded  with  the  statement :  "For  my  part  I  regard  it  as  wholly  dem- 
onstrated that  it  does  occur ;  and  it  must  be  taken  into  account  in 
the  development  of  any  adequate  theory  of  neoplasia." 

^Arch.f.  path.  Aiiat.,  etc.,  (Virchow),  1894,  cxxxviii,  482. 

Beitr.  zur  path.  Anat.,  etc.,  (Ziegler),  1897,  xxii,  587. 
^  Das  chronische  M agengeschwiir ,  etc.,  Leipzig,  1883. 

Das  Cylinder epithel-carcinom,  etc.,  Jena,  1890. 
^  The  Principles  of  Pathology,  Philadelphia  and  New  York,  1910,  Vol.  i,  836. 


BRIEF   HISTORICAL    REVIEW  1 3 

This  view  has  been  adopted  in  part  also  by  Verse/  a  pupil  of  Mar- 
chand,  in  so  far  as  concerned  carcinoma ta  of  the  gastro-intestinal  tract. 

An  account  of  the  argument  between  Ribbert  and  Hauser  may  be 
found  in  an  article  by  the  latter  author,-  whose  paper  is  of  additional 
value  because  it  contains  a  review  of  all  the  cancer  literature  from 
1891  to  1897. 

An  enthusiastic  disciple  of  Ribbert  was  Borrmann;^  who  refuted 
Hauser's  interpretation  of  the  spread  of  carcinoma  and  quoted 
Kokubo,^  Petersen,^  Pforringer,^  and  himself  ^  in  support  of  Ribbert's 
behef  that  cancer  spread  only  through  the  proliferation  of  its  own  cells. 
He  ascribed  the  origin  of  nearly  all  tumors  to  the  growth  of  embrv'onal 
rests,  and  fully  supported  Ribbert's  view  that  an  inflammatory  reac- 
tion always  preceded  the  abnormal  growth  of  epithelium. 

While  Borst  ^  did  not  accord  such  unqualiiied  approval  to  Ribbert's 
hjpo thesis,  he  nevertheless  admitted  that  its  propounder  had  done 
no  inconsiderable  service  in  calling  attention  to  the  many  mistakes 
which  had  been  made  in  explaining  the  transformation  of  normal  into 
abnormal  epithehum  and  by  arousing  pathologists  to  the  too  exclusive 
attention  which  had  been  devoted  to  the  behavior  of  the  epithelium. 
His  own  observations  led  him  to  beheve  that  an  iiiflammatory  infil- 
tration of  the  corium  occurred  almost  without  exception  —  a  true 
h^-perplasia  of  its  connective^  tissue,  however,  not  so  frequently. 
While  both  processes  were  certainly  in  part  secondary  to  the  car- 
cinoma, it  could  not  be  denied  that  inflammation  in  the  subepitheKal 
tissue  might  frequently  afford  the  special  sort  of  stimulation  necessary 
for  the  development  of  such  a  growth.  The  initiatory  invasion,  how- 
ever, was  usually  on  the  part  of  the  epithelium ;  and  although  he  was 
at  variance  with  Ribbert  on  one  point,  he  nevertheless  agreed  entirely 


^  Uber  die  Entstehiing,  den  Ban  u.  das  Wachstum  der  Poly  pen,  Adenome,  n.  Karsinome  des 
Magen-Darmkanals  {Arb.  a.  d.  Path.  Inst,  zii  Leipzig,  1908,  Bd.  i,  Heft  5). 

-  Cenlralbl.  f.  allg.  Path.,  etc.,  1898,  ix,  221. 

^  Zeitschrift  f.  Krebsforsch.,  1904,  ii,  i. 

*  Festschrift  fiir  Orth,  1903.    ' 

^  Beilr.  zur  klin.  Chir.,  (v.  Bruns),  1902,  xxxii,  543. 

^  Beitr.  zur.  klin.  Chir.,  (v.  Bruns),  1904,  xli,  687. 

''  Das  Wachstum  und  die  V erbreitungswege  des  Magencarcinoms,  Jena,  1901.  (Erster 
Supplementband,  Grenzgebiete  der  Medizin  und  Chiriirgie.) 

^  Die  Lehre  von  den  Geschwiilsten,  Wiesbaden,  1902,  ii,  686. 


14  BRIEF   HISTORICAL   REVIEW 

with  Ribbert's  conception  of  the  spread  of  carcinoma,  concluding 
that  the  continuous  cancerous  transformation  of  normal  glands  in  the 
vicinity  of  a  fully  developed  carcinoma  of  a  mucous  membrane  did  not 
occur. 

Janeway  ^  expressed  the  conviction  that  the  great  majority  of 
cutaneous  cancers  were  a  direct  outgrowth  from  normal  epithelial 
cells  and  that  their  development  was  associated  with  insignificant 
changes,  or  no  changes  at  all,  in  the  connective  tissue. 

V.  Hansemann,^  extending  the  observations  of  Klebs,^  investigated 
very  thoroughly  the  types  of  mitoses  found  in  tumor  cells  and  de- 
scribed three  varieties,  distinguished  by  the  amount  of  chromatin 
contained  —  hypochromatic,  normal,  and  hyperchromatic.  He  ex- 
plained the  increased  growth  energy  of  the  cancer  cell  by  postulating  a 
gain  in  the  power  of  independent  proKferation  with  a  concomitant  loss 
of  differentiation ;  this  condition  he  called  anaplasia.  Extensively 
keratinized  cells  in  a  carcinoma  of  the  skin  would  be  less  anaplastic, 
because  departing  less  from  the  normal  type,  than  would  those  of  a 
similar  tumor  that  were  entirely  free  from  keratinization,  while, 
similarly,  an  intestinal  carcinoma  that  still  preserved  some  sem- 
blance of  glandular  arrangement  or  that  contained  cyhndrical  or  goblet 
cells,  would  be  less  anaplastic  than  one  composed  of  polymorphous 
elements.  The  anaplasia  increased  directly  as  the  degree  to  which  the 
cells  were  biologically  removed  from  the  tissue  in  which  they  had  orig- 
inated. It  should  not  be  lost  sight  of,  however,  that  anaplasia  was 
a  relative,  not  an  absolute,  term  —  that  cells  were  not  of  themselves 
anaplastic,  but  only  in  comparison  with  their  mother  tissue.  Nor 
should  anaplasia  be  likened  to  embryonalism  from  which,  on  the 
contrary,  it  was  to  be  sharply  distinguished,  for  embryonal  elements 
were  still  undifferentiated,  while  those  in  a  state  of  anaplasia  had  been 
differentiated  at  one  time  but  had  lost  that  property.  Cells  in  be- 
coming anaplastic  did  not  necessarily  retrace  their  way  over  the  road 
by  which  they  had  departed  from  embryonahsm,  but  rather,  charac- 

^  Zeitschriftf.  Krebsforsch.,  1909-1910,  viii,  403. 

^  Arch.  f.  path.  Anat.,  etc.,  (Virchow),  1890,  cxix,  299. 

Studien  ilber  die  Spezificitdt,  den  AUruismus  iind  die  Anaplasie  der  Zellen,  Berlin,  1893. 

Berl.  klin.  Woch.,  1909,  xliv,  1850. 
^  Die  allg.  Paihologie,  Jena,  1889,  Theil  2,  524. 

Deut.  med.  Woch.,  1890,  xvi,  518. 


BRIEF    HISTORICAL    REVIEW  1 5 

teristics  previously  held  in  abeyance  now  became  able  to  assert  them- 
selves. 

One  of  the  criteria  of  anaplasia  was  an  unequal  division  of  the 
chromosomes  during  mitosis ;  and  if  this  were  followed  by  an  asym- 
metrical division  of  the  cell  it  must  be  assumed,  for  the  following 
reason,  that  elements  of  different  biological  character  would  result. 
In  the  developing  ovum  each  unequal  segmentation  was  followed  by  a 
series  of  equal  divisions  whose  purpose  it  was  to  enlarge  and  perpetu- 
ate characteristic  cell  groups.  The  stages  in  development  at  which 
these  unequal  divisions  occurred  v.  Hansemann  called  generation 
stages.  Every  generation  stage  was  accompanied  or  shortly  followed 
by  a  change  in  the  direction  of  growth  and  by  a  degree  of  differentia- 
tion previously  absent  as,  for  example,  in  the  invagination  of  the  vege- 
tative cells  of  the  blastula  to  form  the  gastrula,  which  was  the  first 
instance  of  the  process  under  discussion.  To  these  generation  stages 
each  asymmetrical  division  of  a  cell  was  comparable,- and  it  was  accord- 
ingly accompanied  by  a  change  in  the  energy  and  the  direction  of 
growth. 

V.  Hansemann  did  not  wish  to  be  understood  as  considering  ana- 
plasia the  prime  cause  of  malignant  proliferation,  since  according  to  his 
conception  a  growth  stimulus  was  required  in  addition.  When  such 
a  stimulus  acted  upon  a  normal  cell  the  result  was  hyperplasia  — 
upon  an  anaplastic  cell,  malignant  growth. 

Those  mitoses  were  asymmetrical  in  which  the  allotment  of  chro- 
mosomes to  the  daughter  stars  was  unequal,  but  as  the  actual  number 
of  chromosomes  going  to  each  diaster  could  not  be  counted  except  in 
rare  instances,  it  was  necessary  to  be  content  with  an  approximate 
estimation.  Irregular  mitoses  v.  Hansemann  believed  characteristic 
of  the  carcinomata,  as  he  had  never  succeeded  in  finding  them  in 
sarcomata,  or  in  hyperplastic,  regenerating,  or  normal  tissue. 

Asymmetrical  mitoses  had,  however,  been  discovered  previously 
by  Podwyssozki  ^  in  the  cells  of  regenerating  liver  tissue,  and  soon 
after  the  appearance  of  v.  .Hansemann's  first  article  further  instances 
of  their  presence  in  cells  other  than  those  of  carcinomata  were  reported. 

Ribbert,^  although  able  to  substantiate  the  occurrence  of  asym- 

^  Beilr.  ziir  path.,  Anat.,  etc.,  (Ziegler),  1886,  i,  301. 
^  Deut.  med.  Woch.,  1891,  xvii,  1183. 


l6  BRIEF    HISTORICAL   REVIEW 

metrical  mitoses  in  carcinoma,  could  not  agree  entirely  with  the  con- 
clusions of  V.  Hansemann  regarding  their  signiiicance,  for  he  had  been 
unable  to  distinguish  between  this  type  of  karyokinesis  and  other  patho- 
logical division  figures.  In  later  articles  Ribbert  ^  denied  the  existence 
of  anaplasia  in  the  sense  of  v.  Hansemann  and  strongly  emphasized 
his  behef  that  the  characteristics  of  cells  were  so  firmly  ILxed  by  hered- 
ity that  single  elements  or  their  ancestors  within  the  same  organism 
could  never  suffer  such  a  radical  change  as  unequal  and  undiffer- 
entiating segmentation. 

Stroebe  -  examined  about  a  dozen  carcinomata  and  found  asym- 
metrical mitoses  present  in  greater  or  smaller  number  without  excep- 
tion, but  was  successful  in  demonstrating  them  also  in  sarcomata,  in 
benign  tumors,  in  heahng  wounds  of  healthy  tissue,  and  in  the  germinal 
centers  of  lymph  nodes.  He  suggested,  therefore,  that  they  were  not 
pecuhar  to  any  special  tissue,  either  pathological  or  normal,  but  were 
to  be  found  in  any  location  where  there  was  a  large  number  of  mitotic 
figures. 

Beneke  ^  beHeved  that  the  mitotic  anomalies  were  secondar)^  to  a 
disturbance  of  specific  functional  cell  power.  In  the  cells  of  mahg- 
nant  new  growths  a  loss  of  function  was  accompanied  by  a  gain  in 
growth  power  and  this  condition,  kataplasia,  constituted  the  only 
difference  between  the  cancer  cell  and  the  normal  element.  In  the 
history  of  developing  cells  there  could  be  no  reversion  and  thus  ana- 
plasia, or  a  return  from  later  to  earlier  stages  through  the  agency  of 
pathological  mitoses,  could  not  possibly  exist. 

V.  Hansemann's  critics  had  attacked  him  by  disputing  both  the 
diagnostic  value  of  irregular  mitoses  and  the  conception  that  anaplasia 
could  give  rise  to  mahgnant  growth.  His  answer  was  that  they  had 
not  read,  or  at  least  had  not  understood,  the  explanations  of  his  hy- 
pothesis. To  the  first  criticism  he  ^  replied  that  the  impossibility  of 
diagnosing  carcinomata  only  by  the  presence  of  pathological  mitoses 
had  been  recognized  and  emphasized  in  his  papers ;   but  because  such 

1  Dent.  med.  Woch.,  1896,  xxii,  471. 

Bihliotheca  Medica,  1897,  Abt.  C,  Heft  9,  32. 
^  Beitr.  zur  path.  Anat.,  etc.,  (Ziegler),  1892,  xi,  i;   1893,  xiv,  154. 
^Arch.f.  path.  Anat.,  etc.,  (Virchow),  1900,  clxi,  100;  1901,  clxiii,  174. 
*  Die  mikroskopische  Diagnose  der  hosartigen  Geschwiilste,  Berlin,  1902,  97,  191. 


BRIEF    HISTORICAL    REVIEW  1 7 

structures  were  not  specific  for  carcinoma  it  did  not  necessarily  follow 
that  the  entire  h>pothesis  should  be  discarded.  To  take  such  a 
course  would  be  "to  pour  out  the  child  with  the  bath."  In  answer 
to  the  second  objection  he  repeated  that  the  h^-pothesis  of  anaplasia 
did  not  concern  itself  with  setiology. 

By  far  the  most  perplexing  attribute  of  the  mahgnant  cell  has  been 
its  capacity  for  unlimited  multiplication.  As  the  study  of  the  cell  pro- 
gressed and  cytologists  became  famiUar  with  the  events  running  their 
course  in  the  fertihzed  egg,  the  fact  seemed  significant  that  segmenta- 
tion did  not  begin  until  another  cell  had  entered  and  fused  with  the 
ovum  after  which,  however,  this  element  became  endowed  with  the 
most  remarkable  proKferative  power.  An  analog}^  between  fertiliza- 
tion and  the  growth  of  the  cancer  cell  seemed  reasonable  and  did 
not  escape  the  observant  mind  of  Virchow/  who  suggested  that  be- 
cause tumor  juices  appeared  to  act  on  certain  elements  as  a  fertihz- 
ing  agent  the  behavior  of  these  tissues  was,  to  this  extent,  entirely 
comparable  to  that  of  the  ovum. 

Leucocytes  had  often  been  described  between  or  even  in  cancer 
cells  and  Klebs  -  suggested  that  they  might,  by  conjugating  with  the 
elements  of  epithelium,  excite  mahgnant  growth. 

Farmer,  Moore,  and  Walker  ^  described  the  occurrence  in  mahgnant 
growths  of  heterot^^ical  mitoses  similar  to  the  ones  found  in  game- 
togenic  cells  and  dift'ering  from  those  of  somatic  cells  in  possessing 
but  one-half  the  number  of  chromosomes  which,  moreover,  assumed 
the  forms_of  rings, Joops,  etc.  They  felt  justified,  therefore,  in  corre- 
lating the  appearance  of  these  gametoid  neoplasms  with  the  result  of 
a  stimulus  which  had  altered  the  normal  somatic  course  of  cell  develop- 
ment into  that  characteristic  of  reproductive  (not  embryonic)  tissue. 

V.  Hansemann^  denied  the  presence  of  heterotypical_mitoses  in 
malignant  growths  and  referred  the  reduction  of  chromosomes  de- 
lineated by  these  authors  to  asymmetrical  mitoses  and  the  degenera- 
tion of  occasional  chromosomes. 


1  Die  krankhaften  Geschwiihte,  Berlin,  1863,  i,  87. 
-  Die  allg.  Pathologic,  Jena,  1889,  Theil  2,  524. 
^  Proc.  Roy.  Soc,  1903,  Ixxii,  499. 

Proc.  Roy.  Soc,  Series  B,  1906,  Ixxvii,  336. 
*Biolog.  Centralbl.,  1904,  xxiv,  189;   1905,  xxv,  151. 


15  BRIEF    HISTORICAL    REVIEW 

While  Bashford  and  ^Murray  ^  at  first  con&rmed  the  findings  of 
Farmer,  Moore,  and  Walker,  dissociating  themselves,  however,  from 
the  conclusions  which  had  been  drawn,  more  extended  observation 
convinced  them  -  that  the  mitoses  of  cancer  were  somatic  rather  than 
heterot}'pical  and  that  the  heterot\^e  appearance  had  been  conferred 
by  variations  in  the  development  of  the  achromatic  figure,  the  peculiar 
forms  of  the  chromosomes,  and  their  mode  of  attachment  to  the 
spindle. 

Walker  and  Whittingham  ^  have  recently  reaflfirmed  the  observation 
of  Farmer,  IVIoore,  and  Walker,  adding  the  statement  that  the  char- 
acteristic shapes  of  the  chromosomes  belonging  to  the  first  meiotic 
(heterotypical)  division  had  been  encountered  in  very  considerable 
numbers  among  the  cells  of  mahgnant  growths. 

Critzmann.^  having  noticed  a  relation  between  twin  births  and 
cancer  in  certain  families,  suggested  that  both  anomalies  resulted  from 
the  development  of  two  ova,  twin  births  following  the  simultaneous 
fertilization  of  two  ova,  cancer  the  inclusion  of  one  of  these  within 
the  other.  A  cancer  was  thus  an  abortive  fetus  retained  ■^'ithin  a 
developed  one  —  the  brother  of  him  who  bore  it. 

De  Morgan  '  concluded  that  in  certain  persons  there  was  a  local 
tendency  toward  tumor  formation,  impressed  upon  the  tissues  perhaps 
during  embr\'onic  life,  but  lying  dormant  until  finally  awakened  by 
irritation.  The  slumber  cell  hypothesis  became  more  wideh-  known, 
however,  through  its  adoption  by  Grawitz,^  according  to  whose  concep- 
tion some  of  the  embryonal  connective  tissue  elements  lost  their  cellular 
nature  and  were  no  longer  demonstrable  T\dth  any  of  the  known  stains. 
They  remained  slumbering  in  this  state,  although  still  taking  part  in 
metaboHsm,  until,  awakened  by  stimulus  or  other  cause,  they  were 
finally  enabled  to  prohferate. 

Beard  ''  modified  Cohnheim's  hypothesis  in  conformity  with  his  own 

^  Proc.  Roy.  Soc,  1904,  Ixxiii,  67. 

^  Proc.  Roy.  Soc,  Series  B,  1906,  Ixxvii,  226. 

*  Jour.  Path,  and  Bad.,  191 1,  x\a,  185. 

^  Le  Cancer.  These  de  Paris,  1S94.     Cited  by  Wolit,  443. 

^  Lancet,  1871,  ii,  155. 

^  Arch.  f.  path.  Anat.,  etc.,  CVirchow),  i89i,cxxvii,  96. 

Berl.  klin.  Woch.,  1892,  xxix,  109. 
^  The  Enzyme  Treatment  of  Cancer,  London,  1911. 


BRIEF    HISTORICAL   REVIEW  1 9 

views  on  the  course  of  normal  development  as  an  alternation  of  asexual 
and  sexual  generations.  He  regarded  cancer  as  an  attempt  of  displaced 
or  aberrant  germ  cells  to  reproduce  the  asexual  phase  of  development 
(the  chorion  in  mammals  and  its  homologue  elsewhere),  while  nor- 
mally the  degeneration  of  the  asexual  generation  was  ascribed  to  the 
activity  of  ferments,  especially  tr>7)sin,  produced  by  the  growing 
embryo.  On  this  series  of  assumptions  he  based  his  advocacy  of  the 
now  discarded  trypsin  treatment  of  cancer. 


CIL\PTER  II 

ATTEMPTS   TO   PRODUCE   TUMORS 

The  possibility  of  inciting  cancer  in  tissues  previously  normal  has 
attracted  and  maintained  the  interest  of  a  large  number  of  experi- 
menters. The  recorded  attempts  are  numerous  and  if.  as  is  probable, 
there  have  been  still  others  which,  because  they  miscarried,  have  not 
been  thought  worthy  of  pubhcation.  the  number  of  times  that  the 
experiment  has  been  made  must  be  very  great.  The  ingenuity  of  man 
has  been  sorely  taxed  to  tmd  ways  of  conferring  the  power  of  mahgnant 
growth  upon  normal  cells  and  the  keenest  intellects  of  two  continents 
have  grappled  with  the  question  year  after  year.  eternaUy  hoping, 
vet  alwavs  baffled.  The  greater  number  of  trials  have  been  molded 
to  ht  one  or  the  other  of  the  two  most  v^ddely  knov^m  h}-potheses  of 
cancer  genesis  —  the  h}-pothesis  of  cell  irritation  and  that  of  cell  dis- 
placement. Following  these  two  h^-pothetical  clues,  investigators  of 
the  question  of  mahgnant  growth  have  irritated  ceUs  or  misplaced  them 
in  everv  conceivable  way.  and  stiU  the  riddle  remains  unanswered  to 
us  as  it  did  to  our  forefathers.  \Miat  relations,  if  any.  obtain  between 
irritation  and  cell  growth  can  hardly  be  re\dewed  here,  but  those 
interested  in  them  may  find  a  fuh  discussion  of  the  question  in  the 
writings  of  Mrchow.  AVeigert.  Ribbert.  and  others.  Xor  can  one 
consider  at  this  point  the  second  hypothesis  which,  fathered  by  the 
great  Cohnheim,  has  become  in  later  years  the  protege  of  Ribbert  and 
his  school, 

A  number  of  pathologists  have  sought  to  initiate  mahgnant  growth 
bv  introducing  the  cells  of  one  animal  into  another.  Xone  of  them, 
however,  has  been  able  to  produce  a  true  neoplasm,  and  the  utter 
hopelessness  of  the  attempt  has  been  emphasized  in  recent  years  by 
the  fact  that  no  malignant  new  growth  has  ever  been  reported  among 
the  thousands  of  mice  and  rats  inoculated  with  normal  tissues  for  the 
purpose  of  conferring  immunity  toward  the  transplantation  of  cancer. 


ATTEMPTS  TO  PRODUCE  TUMORS  21 

Among  the  first  to  attack  in  this  way  the  problem  of  the  origin  of 
cancer  was  Zahn,^  who  transplanted  the  tissues  of  adult  rabbits  into 
other  rabbits  without  a  single  successful  result.  When,  however,  he 
substituted  embryonal  cartilage,  the  grafts  proliferated,  the  amount 
of  growth  being  proportional  to  the  vascularization  of  the  tissues 
surrounding  them.  The  transplantation  of  fetal  bone  was  equally 
successful. 

Leopold,^  who  engaged  in  similar  experiments,  also  found  that 
while  the  tissues  of  young  or  adult  animals  were  quickly  absorbed 
after  transplantation,  fetal  cartilage  would  remain  ahve  and  grow, 
occasionally  reaching  a  size  which  exceeded  by  two  or  three  hundred 
times  that  of  the  original  graft.  In  this  way  there  was  estabhshed  a  true 
enchondroma  which  persisted  for  a  considerable  period.  The  younger 
the  embryos,  the  more  vigorous  was  the  growth  of  their  cartilage. 

Kaufmann^  sewed  in  portions  of  epithehum  of  the  combs  and 
wattles  of  fowl,  and  created  in  this  way  cysts  inclosed  by  a  giant  cell 
tissue  which  grew  very  vigorously  for  weeks  and  exhibited  no  signs  of 
regression  even  after  months  had  passed. 

Martin^  injected  into  the  jugular  vein  of  a  rabbit  oil  of  sweet  almonds 
which  had  been  rendered  irritating  by  the  addition  of  i  to  2  per  cent  of 
croton  oil.  He  discovered  some  time  later  the  existence  of  epithehal 
growths  in  the  lung  recalhng  exactly  in  their  structure  the  type  of 
epithehoma  that  Malassez  had  named  epithelioma  muquotde. 

Hanau,-^  in  the  course  of  protracted  attempts  to  produce  atypical 
epithelial  growth,  painted  various  preparations  of  tar  upon  the  scrotum 
of  white  rats  and  upon  the  vulva,  nipple,  and  mamma  (both  secreting 
and  non-secreting)  of  bitches.  All  of  the  experiments,  however,  were 
entirely  barren  of  result  even  when  irritation  was  kept  up  for  months. 

Considerable  interest  was  aroused  for  a  time  through  the  descrip- 
tion of  an  experiment  by  Lack,^  in  which  he  left  the  scrapings  from  a 

1  Congr.  internal,  des  Sci.  med.  de  Geneve,  1877,  5™^  Session;  Compt.  rend,  el  Memoires. 
Geneve,  1878,  658. 

Arch.f.  path.  Anal.,  etc.,  (Virchow),  1884,  xcv,  369. 
^Arch.f.  path.  Anat.,  etc.,  (Virchow),  1881,  Ixxxv,  283. 
^  Arch.  f.  path.  Anat.,  etc.,  (Virchow),  1884,  xcvii,  236. 
*  Cited  b)-^  Ledoux-Lebard,  Arch.  gen.  de  Med.,  1885,  civ,  423. 
^  Silzungsber.  d.  Gesellsch.  d.  Aerzte  in  Zurich  vom  9  Mdrz,  1889. 

Fortschrilte  der  Med.,  1889,  vii,  338. 
^Journal  Path,  and  Bad.,  1900,  vi,  154. 


22  ATTEMPTS  TO  PRODUCE  TUMORS 

rabbit's  ovary  in  the  peritoneal  cavity  until  the  death  of  the  animal 
fourteen  months  later.  At  the  autopsy,  masses  of  new  growth  exhibit- 
ing the  features  typical  of  ovarian  cancer  were  found  in  the  abdomen 
and  thorax.  Shattock/  however,  pointed  out  that  as  there  was  in 
this  animal  a  uterine  tumor  which  resembled  exactly,  in  the  gross,  a 
columnar  cell  carcinoma  which  he  himself  had  observed  in  the  uterus 
of  a  rabbit,  it  was  at  least  possible  that  the  growths  ascribed  by  Lack 
to  his  experimental  measures  might  have  been  metastases  from  a  primary 
carcinoma  of  the  uterus.  That  such  tumors  in  the  rabbit  are  not  un- 
common may  be  inferred  from  the  fact  that  Boycott^  has  recently 
reported  four  cases  of  epithelial  neoplasm  in  the  uterus  of  this  animal, 
and  Leitch,^  as  well  as  Marie  and  Aubertin,^  spontaneous  carcinomata 
in  the  same  organ. 

Fraenkel  ^  carefully  repeated  Lack's  experiment  fourteen  times,  but 
always  with  an  unsuccessful  issue.  He  further  described  attempts  to 
produce  a  chorion  epithelioma  by  engrafting  rabbit  placenta  into  the 
rabbit  from  which  it  had  been  removed,  into  other  gravid  rabbits,  into 
puerperal  rabbits,  and  into  one  male.  But  not  one  of  these  trials  was 
followed  by  the  outcome  that  he  was  trying  to  procure,  nor  could  he 
detect  any  evidence  of  growth  in  embryonal  ova  after  their  inocula- 
tion. 

Birch-Hirschfeld  and  Garten^  injected  very  young  emulsified  em- 
bryos into  the  livers  of  goats,  rabbits,  fowl,  salamanders,  and  frogs, 
without  being  able  to  induce  the  formation  of  permanent  tumors, 
although  nodules  of  cartilage  did  grow  for  a  time  in  the  Kver  and  lungs 
before  they  were  finally  absorbed.  The  embryonal  cells  underwent  a 
certain  amount  of  differentiation  in  spite  of  their  unusual  environment, 
and  growth  in  the  liver  seemed  to  be  favored  when  that  organ  was 
periodically  stimulated  by  gentle  heat. 

Brosch'''  beheved  that  he  had  succeeded  in  obtaining  atypical  epithe- 
lial growth  as  the  outcome  of  the  following  experiment :   An  area  of 

1  Trans.  Path.  Soc.  London,  1900,  li,  56. 

^  Proc.  Roy.  Soc.  Med.,  1911,  iv,  Path.  Section,  225. 

^  Proc.  Roy.  Soc.  Med.,  191 1,  v,  Path.  Section,  i. 

■*  Bull,  de  V Assoc.  Franq.  pour  V Etude  du  Cancer,  191 1,  iv,  253. 

^  Centralbl.  f.  allg.  Path.,  etc.,  1903,  xiv,  666. 

^  Beitr.  zur  path.  Anat.,  etc.,  (Ziegler),  1899,  xxvi,  132. 

'^  Arch.  f.  path.  Anat.,  etc.,  (Virchow),  1900,  ckii,  72. 


ATTEMPTS  TO  PRODUCE  TUMORS  23 

skin  on  an  animal's  back  was  crushed  between  the  blades  of  a  forceps 
and  a  few  days  later  a  solution  of  paraffin  in  xylol  was  rubbed  into  the 
ulcer  which  remained  after  the  removal  of  the  scab.  Further  appHca- 
tions  were  not  undertaken  until  after  the  infiltration  of  the  wound 
had  receded.  The  atypical  proHferation  was  observed  from  six  to 
ten  weeks  after  the  begirming  of  the  experiment. 

Stahr  ^  noticed  that  rats  fed  for  a  long  time  on  oats  would  develop 
papihary  epithehomata  of  the  tongue,  and  he  traced  these  tumors  to 
the  irritation  set  up  by  the  lodgment  of  small  vegetable  fibers.  The 
same  author-  produced  areas  of  chronic  irritation  in  rabbits,  rats, 
and  mice  by  repeatedly  scraping  a  mucous  membrane  and  painting 
the  eroded  part  with  x>'lol-parafiin,  soot,  or  tar;  still,  in  spite  of 
the  chronic  lesion  thus  induced,  there  had  been  no  evidences  of 
atypical  epithelial  prohferation. 

Kelhng^  denied  that  the  cells  of  mahgnant  growths  originated  in 
the  body  of  the  individual  in  whom  the  tumor  developed,  and  beheved 
rather  that  these  elements  were  cells  of  organisms  lower  in  the  ph^do- 
genetic  scale  which  had  obtained  entrance  and  begun  to  proHferate. 
When  he  submitted  this  hypothesis  to  experimental  proof  he  was 
unable  to  demonstrate  its  vaKdity  to  his  satisfaction  until  the  health 
of  the  animals  had  been  dehberately  undermined  before  inoculation, 
or  until  the  injections  were  made  in  the  neighborhood  of  wounds.  By 
implanting  emulsions  of  flies,  gnats,  snails,  etc.,  he  had  been  successful 
in  producing  a  fibro-sarcoma,  an  adeno-carcinoma,  and  a  mixed  cell 
sarcoma,  and,  furthermore,  in  recognizing  in  some  cases  the  cells  of  the 
organism  introduced.  In  the  following  year  he  ^  described  the  evolu- 
tion of  other  mahgnant  tumors  in  five  out  of  seven  dogs,  through  the 
inoculation  of  fowl  embryos  emulsified  in  sahne  solution.  None  of 
Kelhng's  observations  have  received  any  widespread  acceptance. 

Ribbert  °  obtained  small  but  typical  papillomatous  growths  on  the 
inner  surface  of  the  rabbit's  hp  by  repeatedly  scraping  certain  points, 
again  denuding  them  as  often  as  the  epithelium  was  regenerated,  and 

1  Centralhl.  f.  allg.  Path.,  etc.,  1903,  xiv,  4. 
^  Munch,  med.  Woch.,  1907,  liv,  1178. 
^  Wien.  med.  Woch.,  1903,  liii,  1431. 
Miinch.  med.  Woch.,  1903,  1,  923. 
^  Miinch.  med.  Woch.,  1904,  li,  1047,  1909. 
^  Geschwtilsllehre,  Bonn,  1904,  352. 


24  ATTEMPTS  TO  PRODUCE  TUMORS 

finally  allowing  them  to  heal.  It  appeared  that  a  state  of  chronic 
inflammation  played  an  important  role  in  the  causation  of  this  and 
other  types  of  fibro-epithelial  tumors,  for,  as  Ribbert  remarked,  when 
irritation  and  inflammation  had  ceased  tumors  of  this  class  not  infre- 
quently retrogressed. 

Loeb^  injected  or  transplanted  portions  of  embryos  into  adult 
animals  with  the  general  result  that  most  of  the  tissues  not  only  grew, 
but  even  underwent  a  certain  amount  of  differentiation.  Thus  epithe- 
lial cells  arranged  themselves  in  glandular  form  and  could  be  seen  to 
contain  granules  denoting  cell  activity.  As  in  the  experiments  of 
Zahn  and  Leopold,  the  most  pronounced  growth  was  observed  in  the 
case  of  cartilage.  The  implantation  of  adult  tissues  afforded  analogous 
results  except  that  growth  on  the  part  of  cartilage  was  not  so  marked. 
With  tissues  other  than  cartilage  embryonal  cells  did  not  proliferate 
more  actively  than  those  from  animals  fully  grown,  and,  indeed,  in 
some  cases  the  adult  elements  seemed  to  grow  even  more  vigorously 
than  the  others.  The  data  thus  acquired  did  not,  therefore,  justify  the 
widely  accepted  idea  that  embryonal  tissues  were  greatly  superior 
to  adult  in  their  power  to  proliferate  after  transplantation.  In  all 
of  the  experiments  the  displaced  cells  finally  ceased  to  grow  and  even- 
tually underwent  absorption.^  The  same  author  ^  succeeded  in  produc- 
ing, in  the  uterus  of  the  guinea-pig,  nodules  of  decidual  tissue  possessing 
the  power  of  temporary  growth.  Incisions  were  made  into  the  pregnant 
uterus,  sometimes  in  various  directions,  while  at  other  times  part  of 
one  horn  was  spKt  longitudinally  and  the  mucous  membrane  everted. 
When  the  uterus  was  thus  incised  on  the  fifth  or  sixth  day  of  pregnancy 
there  developed  in  the  wounds  a  number  of  nodules  composed  of  typi- 
cal decidual  tissue.  Immediate  contact  with  the  ovum  was  evidently 
not  necessary,  for  serial  sections  of  a  number  of  these  "  deciduomata  " 
were  searched  in  vain  for  embryos.  In  experiments  prosecuted  during 
earlier  or  later  stages  of  pregnancy  decidual  nodules  were  not  evolved, 
although  small  ones  could  still  be  produced  as  late  as  the  tenth  day, 
and  in  one  case  followed  an  operation  undertaken  during  the  first  two 

^  Jour.  American  Med.  Assoc,  1903,  xl,  974. 

2  It  is  not  quite  clear  whether  these  experiments  were  done  by  Loeb  himself,  or  whether 
the  author  is  recapitulating  the  work  of  others. 
^  Centralbl.  f.  dig.  Path.,  etc.,  1907,  xviii,  563. 


ATTEMPTS  TO  PRODUCE  TUMORS  25 

days.  From  three  to  four  weeks  after  operation  the  nodules  were 
partly  or  entirely  necrotic. 

Commenting  on  the  relation  between  these  nodules  of  decidua  and 
the  malignant  tumors,  Loeb  ^  said  that  during  the  early  period  of  its 
existence  the  corpus  luteum  secreted  a  chemical  body  which  united 
with  the  mucosa  of  the  uterus  and  sensitized  it.  When  incisions  were 
made  into  the  uterus  the  freeing  of  its  inner  surface  from  tension  acted 
as  an  external  stimulus  which  caused  the  sensitized  tissue  to  react 
with  the  production  of  tumor-like  formations,  where  under  ordinary 
conditions  the  uterus  would  have  shown  only  the  usual  processes  of 
wound  healing.  For  the  initiation  of  malignant  growth,  therefore,  one 
factor  alone  did  not  always  suffice.  There  were  necessary  a  chemical 
sensitizing  substance  and  an  external  exciting  cause  —  facts  which 
must  be  kept  in  mind  in  attempting  to  interpret  the  origin  of  cancer. 

The  experiments  of  Wilms  ^  concerned  the  implantation  of  five-to- 
seven-day-old  embryo  chicks  into  young  fowl,  a  procedure  which  was 
followed  by  considerable  growth  and  differentiation.  In  trying  to 
overcome  the  reaction  against  the  newly  introduced  cells,  by  making 
several  successive  inoculations  at  intervals  of  eight  days,  Wilms  gained 
the  impression  that  more  energetic  development  took  place.  There 
seemed  to  be  a  certain  disposition  favorable  to  growth  in  one  of  the 
birds,  for  all  of  the  grafts  had  developed  into  palpable  nodules  at  a  time 
when  those  in  five  other  birds  were  still  indistinguishable.  As  in  the 
experience  of  other  investigators,  so  there  occurred  here  a  certain  tem- 
porary growth  and  differentiation  of  the  embryonal  tissue  in  spite  of  its 
new  surroundings,  succeeded  by  final  regression  and  entire  absorption. 

Careful  and  extensive  experiments  of  the  same  type  were  undertaken 
by  Nichols  ^  to  determine  whether  normal  tissue  could  acquire  after 
transplantation  the  power  of  unHmited  growth  and  give  rise  to  metasta- 
ses. Rabbits  and  guinea-pigs,  sixty-two  in  all,  were  inoculated  with  the 
cells  of  various  organs  but  always  with  an  unsuccessful  issue,  at  least 
in  so  far  as  unlimited ,  proHferation  and  the  production  of  metastases 
were  concerned,  although  occasionally  the  implanted  structures  were 
possessed  of  enough  proliferative  energy  to  give  origin  to  growths  re- 

1  New  York  Med.  Jour.,  1909,  xc,  145. 

2  Verhandl.  d.  deiitschen  path.  Gesellsch.,  1904,  8  ^  Tagung,  79. 
^  Jour.  Med.  Research,  1904-1905,  N.S.,  viii,  221. 


26  ATTEMPTS  TO  PRODUCE  TUMORS 

sembling  dermoid  cysts  or  teratomata.  The  materials  used  included 
testis,  ovary,  kidney  cortex,  Hver  epithelium  (adult  and  fetal), 
adrenal  gland,  adult  or  fetal  epidermis,  adult  uterine  epitheUum  from 
pregnant  and  non-pregnant  animals,  fetus  (entire) ,  fetal  cartilage, 
and  placenta.  Among  all  these  tissues  only  adult  and  fetal  epidermis, 
uterine  epithehum,  entire  fetus,  cartilage,  and  placenta  were  capable  of 
proliferation ;  these  produced  tumors  which  varied  in  size  from  a  small 
nodule  to  one  exceeding  by  ten  or  twenty  times  the  amount  intro- 
duced, but  not  one  of  which  was  at  all  comparable  to  a  true  mahgnant 
growth. 

In  an  endeavor  to  create  tumors  from  normal  cells  already  possess- 
ing, or  supposed  to  possess,  high  proliferative  power,  Levin  ^  implanted 
or  injected  rabbits  with  cells  from  the  ovary,  with  embryonic  cells  or 
those  from  healing  wounds  in  the  adult  hver,  with  epithehum,  and 
with  pigmented  cells  from  the  iris.  In  no  case,  however,  could  he 
convince  himself  that  any  of  the  elements  so  transplanted  had  taken 
on  mahgnant  growth. 

Reinke^  recorded  an  example  of  at3q3ical  epithelial  growth  which 
he  had  procured  by  the  injection  of  4  %  ether  into  the  eye  of  the 
adult  salamander.  The  proHferating  epithehum  of  the  crystalline  lens 
thus  obtained  was  transplanted  intraperitoneally  into  other  sala- 
manders, where  it  continued  its  growth,  lost  its  similarity  to  lens  epithe- 
lium, and  finally  came  to  resemble  carcinoma.  Reinke  had  found,  also, 
that  the  mitosis  educed  by  treatment  with  ether  could  be  inhibited. 
He  rubbed  down  salamander  lens  with  ether,  which  he  poured  off  and 
allowed  to  evaporate,  afterward  making  a  sahne  emulsion  of  the  residue 
so  gained.  This  he  inoculated  into  the  eyes  of  salamanders  that  had 
undergone  an  injection  of  4  %  ether  eight  days  previously  and  found 
subsequently  no  mitoses,  or  only  a  few  at  the  most.  The  conclusion 
was  accordingly  drawn  that  there  was  present  in  the  tissues  a  ma- 
terial which  inhibited  mitotic  division  and  which  could  be  extracted 
with  ether.  The  continued  action  of  ether  upon  normal  cells  dissolved 
this  substance  or  altered  it  in  such  a  way  as  to  permit  the  occurrence  of 
mitotic  division  or  atypical  growth ;  but  if  the  material  were  supphed 

1  Jour.  Med.  Research,  1901,  N.S.,  i,  145. 

2  Deutsche  tnedismal  Zeitung,  1907,  xxviii,  579. 
Munch,  med.  Woch.,  1907,  liv,  2381. 


ATTEMPTS  TO  PRODUCE  TUMORS  27 

in  sufficient  amount,  it  could  be  taken  up  anew  by  the  cells  and  again 
exert  its  inhibitory  action  upon  division. 

Askanazy/  stimulated  by  these  experiments,  mixed  emulsions  of 
rat  embryo  with  4  %  ether  before  inoculation,  and  obtained  a  series 
of  large  rapidly  growing  teratoid  tumors  such  as  he  had  never  seen 
following  the  inoculation  of  untreated  embryos,  even  in  pregnant 
animals.  The  fat  stain,  Scharlach  R,  which  Fischer  believed  capable 
of  exciting  epithelial  growth  exerted,  on  the  contrary,  an  inhibitory 
effect  upon  the  proliferation  of  embryonic  tissue. 

Freund-  succeeded  in  producing  teratoid  tumors  in  74%  of  rats 
that  had  been  inoculated  intraperitoneally  with  an  emulsion  of  rat 
embryo.  The  age  of  the  injected  rats  was  immaterial,  but  the  results 
were  more  uniformly  successful  in  females.  Previous  treatment  of  the 
embryo  tissues  with  ether  water  or  with  solutions  of  indol  with  or 
without  ether  had  no  effect  upon  their  subsequent  proliferation,  nor 
was  growth  any  more  vigorous  after  autoplastic  than  after  homoplastic 
transplantation.  Finally,  tumors  followed  the  intraperitoneal  in- 
oculation of  animals  in  which  subcutaneous  injection  had  been  un- 
successful, a  fact  proving  that  resistance  had  not  been  conferred  by 
the  single  antecedent  unsuccessful  treatment. 

V.  Hippel  ^  observed  the  evolution  of  a  teratoma  from  the  head  of  a 
twelve-day-old  rabbit  embryp  which  had  been  injected  as  a  saline 
emulsion  into  the  eye  of  an  adult  rabbit.  Six  weeks  after  the  begin- 
ning of  the  experiment,  the  tumor  had  reached  a  length  of  i  centimeter 
and  a  thickness  of  0.8  centimeter  and  was  composed  of  elements  of  the 
outer  and  middle  germinal  layers,  but  contained  none  of  the  tissues  of 
the  hypoblast. 

Embryos  were  transplanted  into  adult  animals  by  v.  Tiesen- 
hausen  ^  also.  In  his  earlier  experiments  he  made  use  of  mammalian 
material,  but  in  later  investigations  he  employed  the  chick,  because 
of  the  readiness  with  which  embryos  of  known  age  could  be  procured 
from  artificially  incubated  eggs.     About  one  hundred  and  fifty  inocu- 

^  Wien.  med.  Woch.,  1909,  lix,  2518,  2578. 

CentralU.f.  allg.  Path.,  etc.,  1909,  xx,  1039. 
^  Beitr.  zur  path.  Anat.,  etc.,  (Ziegler),  1911,  li,  490. 
'  Verhandl.  d.  deutschen  path.  Gesellsch.,  1906,  lo*^^  Tagung,  56. 
^  Arch.  f.  path.  Anat.,  etc.,  (Virchow),  1909,  cxcv,  154. 


28  ATTEMPTS  TO  PRODUCE  TUMORS 

lations  were  made  into  young  and  old  fowls  at  different  sites  with 
chicks  varying  in  age  from  one  to  eight  days.  Five-day  embryos  gave 
the  best  results,  whereas  inoculation  with  those  less  than  two  days  old 
was  attended  by  a  uniformly  negative  outcome.  The  sites  chosen  for 
implantation  included  the  anterior  and  posterior  chambers  of  the  eye, 
the  brain,  the  pectoral  muscles,  the  anterior  abdominal  wall,  the  great 
omentum,  the  peritoneal  cavity,  the  comb,  and  the  wattles.  In  no 
case  was  progressive  growth  obtained,  even  in  the  birds  from  which 
the  chick  embryos  had  been  derived,  nor  were  any  metastatic  deposits 
observed.  Growth  went  on  actively  for  about  eight  weeks,  but  grad- 
ually ceased  after  from  six  to  twelve  months. 

Fichera  ^  inoculated  rats  subcutaneously  with  a  bouillon  suspension 
of  rat  embryos,  causing  nodules  which  grew  progressively  until,  at  the 
expiration  of  two  or  three  months,  they  were  at  least  twenty  times  the 
original  size.  But  by  the  end  of  six  months  their  volume  had  greatly 
diminished,  and  they  could  not  be  considered  in  any  sense  as  malignant 
new  growths.  When  several  successive  inoculations  had  been  made 
grafts  became  necrotic  as  early  as  the  tenth  day. 

The  question  whether  pregnant  animals  might  not  perhaps  offer  a 
more  favorable  soil  for  the  growth  of  embryonic  tissue  has  not  escaped 
investigation.  Askanazy  -  and  his  pupil  Jentzer  ^  thought  that  preg- 
nancy in  the  host  exerted  a  distinctly  adjuvant  effect  upon  the  growth 
of  experimental  teratomata  in  white  rats,  and  Fere  ^  noticed  increased 
growth  in  brooding  hens ;  but  Shattock,  Sehgmann,  and  Dudgeon,^  on 
the  contrary,  did  not  find  that  the  proKferation  of  ingrafted  fetal 
cartilage  was  stimulated  in  rabbits  that  repeatedly  bore  young. 

Rous  ^  cited  certain  investigations  of  Fichera  ^  which  seemed  to  es- 
tabHsh  the  fact  that  embryonic  grafts  grew  better  in  the  rats  from 
which  they  had  been  removed  than  they  did  either  in  non-pregnant 
or  in  other  pregnant  rats.     The  observations  of  Rous,  which  were 

^  Arch,  de  Med.  exp.  et  d^Anat.  path.,  1909,  xxi,  617. 

2  Verhatidl.  d.  deiitschen  path.  Gesellsch.,  1907,  11  ^  Tagung,  82. 

^  Rev.  med.  de  la  siiisse  Romande,  1908,  xxviii,  329. 

*  Compt.  rend.  Soc.  Biol.,  1899,  li,  824;    1900,  Hi,  737. 

^  Proc.  Roy.  Soc.  Med.,  1909-1910,  iii,  Path.  Section,  132. 

^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1909-1910,  vii,  71. 

Jour.  Exp.  Med.,  1911,  xiii,  248. 
^  Policlinico,  Sez.  pratica,  1909,  xvi,  692. 

Etiologia  del  cancro,  Rome,  1909. 


ATTEMPTS  TO  PRODUCE  TUMORS 


29 


undertaken  independently  of  Fichera's,  demonstrated  that  embryonic 
mouse  tissue  obtained  at  operation  and  implanted  in  the  mother 
would  grow  well  if  she  no  longer  carried  young ;  and  although  growth 
was  no  more  rapid  than  in  favorable  non-pregnant  aliens,  yet  it  per- 
sisted for  a  longer  period  and  resulted  in  a  greater  variety  of  tissues. 
On  the  other  hand,  when  a  mouse  still  bearing  embryos  was  implanted 
with  embryonic  tissues  from  her  own  uterus  the  grafts  failed  either  to 
grow  or  to  differentiate,  although  they  did  become  vascularized.  Still, 
they  did  not  die,  and  sometimes  proliferation  was  inaugurated  after 
the  conclusion  of  pregnancy. 

Freund  ^  concluded  that  pregnant  rats  offered  a  somewhat  more 
suitable  soil  for  the  growth  of  embryo  emulsions  than  did  non-preg- 
nant females,  although  the  difference  amounted  to  but  2  %. 

Rous  -  investigated  in  mice  the  behavior  of  embryonal  cells  mixed 
with  tumor,  hoping  that  as  some  transplantable  carcinomata  were  able 
to  originate  sarcomatous  transformation  in  their  stroma,  so  close  asso- 
ciation with  tumor  cells  might  cause  embryonic  tissue  to  assume  ma- 
lignant properties.  He  found  that  growth  of  both  components  took 
place  and  that  there  was  often  an  intimate  histological  association  of 
the  two ;  but  for  the  occurrence  of  these  conditions  a  balance  of  avidity 
was  necessary,  otherwise  the  embryonic  cells  were  necessarily  soon 
overgrown  by  those  of  the  rnore  rapidly  proliferating  tumor.  It 
seemed,  therefore,  that  the  enormous  proliferative  capacity  exhibited 
by  embryonic  tissue  in  lUero  depended  at  least  as  much  upon  the  ex- 
cellent nutritive  arrangement  as  upon  inherent  cell  energy.  In  a 
mixed  graft  that  had  only  partially  succeeded,  tumor  and  embryo 
tended  to  grow  or  to  fail  together,  while  in  a  number  of  quantitative 
experiments  it  was  found  that  tumor  and  embryo  proliferated  better 
alone  than  when  mixed. 

Gougerot  and  Laroche  ^  obtained  a  keloid  in  a  tubercular  guinea- 
pig  at  the  point  where  an  inoculation  of  tuberculin  had  been  made. 
The  ridge  of  growth  was  twenty-five  milHmeters  long  and  five  milH- 
meters  wide,  appeared -to  involve  the  needle  track,  and  when  excised 

1  Beitr.  zur  path.  Anat.,  etc.,  (Ziegler),  191 1,  li,  490. 
^  Proc.  Soc.  Exp.  Biol,  afid  Med.,  1909-1910,  \-\i,  73. 

Jour.  Exp.  Med.,  1911,  xiii,  239. 
^  Compt.  rend.  Soc.  Biol.,  1908,  Ixv,  342. 


30  ATTEMPTS  TO  PRODUCE  TUMORS 

and  examined,  was  found  to  consist  of  collagenous  fibers  inclosing  a 
few  cells.  This  case  was  the  sole  success  in  a  long  series  of  experi- 
ments upon  fourteen  guinea-pigs. 

The  development  of  sarcoma  in  a  rat  that  had  been  exposed 
repeatedly  to  X-rays  was  reported  by  Clunet.^  Fragments  of  the 
growth  were  transplanted  into  eight  rats,  in  one  of  which  there  was 
found  a  nodule  the  size  of  a  pea  about  two  months  after  inoculation. 
Recession,  however,  set  in  immediately,  and  two  months  later  the 
tumor  had  disappeared  entirely. 

Considerable  discussion  has  ensued  upon  Fischer's  description  ^  of  a 
series  of  experiments  in  which  he  had  succeeded  in  producing  lesions 
imitating  very  closely  the  histological  structure  of  carcinoma.  After 
having  failed  to  produce  a  suitable  irritation  by  means  of  agar  impreg- 
nated with  calcium  salts  he  tried  a  saturated  solution  of  the  stain 
Scharlach  R  in  olive  oil,  injecting  it  into  the  ears  of  rabbits  just  beneath 
the  epithelium  and  under  considerable  pressure.  After  a  few  days  an 
augmented  number  of  mitoses,  of  which  a  few  were  atypical,  was 
detected  in  the  germinal  layer  of  the  epithelium,  hair  follicles,  and 
sebaceous  glands,  and  there  was  an  increase  in  the  thickness  of  the 
whole  epithelial  layer  with  an  attendant  over-production  of  keratin. 
In  later  stages  the  epithelial  proHferation  was  still  more  marked, 
hair  follicles  and  sebaceous  glands  had  either  disappeared  or  become 
strands  of  squamous  epithelium,  and  these  structures  then  began 
to  invade  the  underlying  parts.  When  the  intrusions  reached  the 
particles  of  oil  lying  in  the  connective  tissue  the  epitheHum  grew 
around  the  globules  in  an  irregular  way,  producing  a  lesion  which  in 
appearance  was  comparable  only  to  a  squamous  cell  carcinoma  in  man. 
Such  areas  could  not,  however,  be  called  true  epitheUomata  because 
they  were  not  destructive  and  because,  furthermore,  growth  did  not 
continue  after  the  oil  had  been  absorbed.  It  was  found  that  the  two 
fat  stains  Sudan  III  and  indophenol,  chemically  unrelated  though  they 
were,  exerted  a  similar  action.  A  series  of  experiments  on  the  epithe- 
lium of  the  stomach,  intestine,  and  mamma,  had  been  inaugurated,  but 
at  the  time  of  writing  the  subepithelial  inflammation  resulting  from 

1  Recherches  exp.  siir  les  Tumeurs  malignes,  Paris,  1910,  297. 

2  Verhandl.  d.  deutschen  path.  Gesellsch.,  1906,  lo*^^  Tagung,  20,  22. 
Munch,  med.  Woch.,  1906,  liii,  2041. 


ATTEMPTS    TO    PRODUCE    TLTIORS  3 1 

the  inoculation  of  solutions  of  Scharlach  R  produced  no  trace  of  epi- 
thelial growth  in  these  locations.  Other  solutions  of  the  dye  were  in- 
vestigated, among  them  a  saturated  ethereal  solution  which  was  injected 
into  four  of  the  mammary  glands  of  a  rabbit.  In  all  four,  numerous 
lobules  were  transformed  into  islets  and  strands  of  squamous  epithe- 
lium of  exactly  the  same  shape  as  a  gland  lobule  and  connected  with 
the  duct.  It  seemed  most  probable  that  the  parenchyma  had  been 
destroyed  and  then  replaced  through  regeneration  (often  of  duct  epi- 
thelium), and  that  during  the  process  there  had  resulted  the  substitu- 
tion of  squamous  epithehum  for  gland  lobules.  No  such  lesions  were  to 
be  found  in  the  mammae  that  had  not  been  injected.  To  explain  the 
action  of  Scharlach  R  Fischer  suggested  that  there  might  be  a  specific 
substance  —  an  attraxin  —  contained  in  it,  able  to  exercise  a  posi- 
tive chemotactic  influence  on  epitheHal  cells.  The  growth  of  the  epi- 
thehum about  the  oil  globules  could,  at  any  rate,  hardly  be  explained 
by  the  weU-known  disposition  of  epithehum  to  grow  along  a  free  surface, 
for  it  did  not  take  place  about  collections  of  other  oils  and  fats ;  and, 
moreover,  if  Scharlach  R  exerted  only  an  ordinary  stimulus  upon 
the  epithehum  it  was  hard  to  see  why  the  effects  above  set  forth  did 
not  follow  its  external  apphcation,  even  when  this  was  continued  for 
months.  The  demonstration  of  a  chemotactic  action  on  the  part  of 
the  dye  seemed  to  Fischer,  therefore,  the  most  significant  feature  of 
the  experiment,  and  pursuing  his  h;ypothesis  further  he  interpreted 
the  hmitless  growth  of  malignant  tumors  as  the  product  of  a  hypotheti- 
cal attraxin  occurring  naturally  and  exerting  its  influence  upon  em- 
bryonal cell  rests. 

McCoimell,^  in  repeating  these  experiments  with  rabbits.  Belgian 
hares,  guinea-pigs,  and  white  rats,  found  that  Belgian  hares  were  on 
the  whole  the  most  suitable  animal  in  which  to  reproduce  the  lesions 
described  by  Fischer. 

Jores-  pubHshed  a  general  confirmation  of  Fischer's  results  in  which, 
however,  he  laid  somewhat  more  stress  upon  the  role  which  was  played 
by  the  germinal  epithehum  of  the  hair  folhcles.  Indeed,  when  moderate 
pressure  had  been  employed  the  outcome  of  the  injection  was  mainly 
a  prohferation  of  this  layer,  and  the  h3'pertrophy  of  the  surface  epi- 

1  Jour.  American  Med.  Assoc,  1907,  xlix,  1498. 
^  Miinch.  med.  Woch.,  1907,  liv,  879. 


32  ATTEMPTS  TO  PRODUCE  TUMORS 

thelium  occurred  only  when  the  oil  had  been  injected  under  greater 
pressure.  The  sebaceous  glands,  at  first  unaffected,  were  gradually 
lost  to  \-iew  amid  the  encroaching  hair  foUicles.  If  the  epithehal 
growth  exceeded  a  mere  thickening  of  the  hair  foUicles  a  lesion  of 
cancerous  appearance  was  the  result ;  still,  such  a  condition  was  difficult 
of  attainment  and  Jores  had  seen  it  only  once.  He  had  never  been 
able  to  reproduce  it  in  scar  tissue  even  after  repeated  injections,  pos- 
sibly because  of  the  absence  of  hair  follicles.  The  process  as  a  whole 
seemed  to  be  the  sum  of  two  components  —  action  b}^  the  dye  upon 
the  upper  part  of  the  hair  follicles,  and  proliferation  of  the  epithehum 
which  lay  in  direct  contact  with  the  oil  globules.  The  latter  phenom- 
enon one  might  be  tempted  at  first  to  refer  to  the  tendenc}^  of  epi- 
thelium to  grow  over  any  surface.  But  particles  of  Scharlach  oil  were 
more  readily  inclosed  than  other  foreign  bodies,  a  fact  which,  in  con- 
junction with  the  characteristic  action  of  the  stain  upon  the  hair 
foUicles,  led  the  author  to  assign  to  the  dye  an  actual  influence 
upon  squamous  epithelium,  although  it  might  not  be  chemotactic. 
It  was  very  unlikely,  too,  that  Scharlach  R  exerted  any  real 
stimulus  to  growth,  and  the  proliferation  attending  its  injection 
might  be  considered  with  more  justification  as  a  replacement  process 
exceeding,  in  the  manner  described  by  Weigert,  the  bounds  of 
physiological  regeneration. 

Hehnholz^  confirmed  and  extended  the  experiments  begun  by 
Fischer,  and  proved  that  the  eff'ects  of  Sudan  III  and  Scharlach  R 
were  exercised  not  only  upon  various  t^pes  of  epithehum  but  also 
upon  those  connective  tissues  which  produce  cartUage.  He  did  not 
adopt,  however,  the  conclusions  which  Fischer  had  drawn,  and  expressed 
the  behef.  not  that  the  dyes  possessed  a  specific  attraxin.  but  rather 
that  they  contained  some  substance  which,  by  interaction  with  con- 
nective tissue,  produced  a  soU  appropriate  for  epithehal  develop- 
ment. 

In  contrast  to  the  foregoing  workers  Snow  -  could  not  substantiate 
Fischer's  observ-ations.  although  it  should  be  noted  that  his  injections 
were  not  made  under  the  high  pressure  upon  which  Fischer  had 
insisted. 

^  Johns  Hopkins  Hasp.  BidL,  1907,  xvnii,  365,  369. 
^  Jour.  Infect.  Diseases,  1907,  iv,  3S5. 


ATTEMPTS  TO  PRODUCE  TUMORS 


33 


Stahr/  on  the  other  hand,  was  able  to  corroborate  Fischer,  but  only 
by  following  strictly  the  technic  which  that  author  had  described ; 
wherefore  he  emphasized  the  necessity  of  injecting  the  oil  under  very 
high  pressure.  He  found  that  atypical  epithelial  growth  would  follow 
even  a  single  injection  of  a  saturated  solution  of  Sudan  III  in  oHve  oil. 
While  Stahr's  results  were  thus  confirmatory,  he  disagreed  with 
Fischer's  theory  of  a  specific  chemotactic  action  and  was  inclined  to 
refer  the  lesions  to  the  co-result  of  a  stimulus  plus  a  complex  of  condi- 
tions, not  the  least  among  the  latter  being  the  anatomical  structure 
of  the  tissue  into  which  the  dye  had  been  injected. 

Wyss-  had  concluded  from  observations  on  X-ray  carcinomata 
that  such  tumors  were  consequent  upon  altered  nutrition,  and  this 
upon  a  narrowing  or  obliteration  of  the  subepithelial  blood  vessels 
supplying  a  certain  group  of  cells.  Areas  deprived  of  nourishment 
in  this  way  underwent  proliferation  and  finally  became  parasitic  on 
the  neighboring  tissues.  Wyss  believed  that  the  proliferation  described 
by  Fischer  was  not  due  to  chemotactic  influences  but  to  a  withdrawal 
of  normal  nutrition  through  the  obhteration  of  blood  vessels,  and 
emphasized  the  fact  that  the  most  striking  results  were  seen  after 
injection  had  been  made  at  high  pressure. 

Levin  ^  investigated  in  white  rats  the  action  of  a  saturated  solution 
of  Scharlach  R  in  paraffin  or  oil  when  injected  subcutaneously  or  into 
the  mamma.  Only  in  the  connective  tissue  elements  could  any  proHf- 
eration  be  demonstrated,  an  observation  well  in  accord  with  a  previous 
finding  by  the  same  author,^  that  the  rat  was  prone  to  vigorous  reac- 
tions on  the  part  of  its  connective  tissues. 

Seyberth '"  confirmed  the  observation  of  Rehn,  that  tumors  of  the 
bladder  were  not  infrequent  among  those  who  worked  in  anihne  dye 
factories,  and  recorded  five  such  cases,  three  non-malignant  although 
showing  excessive  epithehal  prohferation,  and  two  mahgnant.  Of 
the  latter,  one  was  an  adeno-carcinoma  and  the  other  a  carcinoma. 
These  growths,  the  author  beheved,  were  all  without  doubt  the  prod- 

^  Miinch.  med.  Woch.,  1907,  liv,  11 78. 
^  Miinch.  med.  Woch.,  1907,  liv,  1576. 
^  Jour.  Exp.  Med.,  1908,  x,  815. 
^  Med.  Record,  1907,  Ixxii,  974. 
^  Miinch.  med.  Woch.,  1907,  liv,  1573. 


34  ATTEMPTS  TO  PRODUCE  TUMORS 

uct  of  one  cause,  namely,  chronic  stimulation  of  the  bladder  wall  by 
urine  containing  aniline  bodies,  and  Fischer's  experiments  had  thrown 
a  significant  light  upon  the  relations  between  aniline  dyes  and  epi- 
thelial proliferation. 

Stoeber^  experimented  with  certain  components  of  Scharlach  R  and 
Sudan  III,  all  of  which  were  found  to  elicit  epithehal  prohferation. 
Some  of  these,  however,  which  were  toxic,  and  others  which  caused 
necrosis,  were  of  course  unsuitable  for  further  investigation.  Con- 
trary to  Fischer's  behef  the  chief  source  of  the  new  epithehum  was  not 
the  surface  layer  but,,  as  Jores  had  contended,  the  germinal  epithelium 
of  the  hair  follicles.  The  same  writer  ^  recorded  the  next  year  an  ex- 
periment in  which  oily  solutions  of  Scharlach  R,  amidoazo toluol,  and 
a-naphthylamine  had  been  inoculated  into  the  foot  of  an  old  man 
with  ununited  fracture  of  the  leg,  before  amputation.  When  this  was 
performed  fourteen  days  later  it  was  found  that  Scharlach  R  and 
amidoazotoluol  had  induced  epithelial  changes  identical  with  those 
evolved  in  the  rabbit's  ear.  They  were  not  so  extensive,  however, 
partly  because  hair  follicles  and  sebaceous  glands  were  only  sparsely 
distributed  in  the  inoculated  region.  The  overlying  epithelium  was 
thickened,  and  the  down-growing  projections  appeared  to  have  been 
derived  from  thickened  hair  folKcles  and  the  ducts  of  sweat-glands. 
No  sebaceous  glands  were  recognized  in  the  sections. 

In  conjunction  with  Wacker,^  Stoeber  sought  to  discover  what 
effect  would  follow  the  injection  of  various  products  found  in  the  body 
under  physiological  or  pathological  conditions,  and  especially  of  such 
as  resulted  from  the  splitting  and  decomposition  of  albumins.  It  was 
apparent  that  only  organic  substances  of  a  basic  nature  and  soluble  in 
fats,  had  any  definite  action  upon  epithehum.  Employing  Fischer's 
technic,  but  using  small  amounts  and  making  two  injections  with  two 
or  three  days  intervening,  the  authors  obtained  epithelial  proliferation 
with  2  and  5  %  solutions  of  pyridin  in  olive  oil,  and  with  5  %  indol 
or  skatol  in  rabbit  fat.  The  inoculation  of  indol  solution  followed  by 
a  small  amount  of  skatol  produced  a  tumor  which  attained  the  size  of 
a  hazel-nut  within  fifteen  days.  The  histology  of  the  lesions  provoked 
by  pyridin  were  less  characteristic  than  in  the  case  of  indol  and  skatol. 

^  Miinch.  med.  Woch.,  1909,  Ivi,  129.  ^  Milnch.  med.  Woch.,  1910,  Ivii,  739. 

^  Munch,  med.  Woch.,  1910,  Ivii,  947. 


ATTEMPTS  TO  PRODUCE  TUMORS  35 

The  picture  produced  by  the  two  last  mentioned  was  similar  to  that 
of  human  squamous  cell  carcinoma,  so  similar,  indeed,  that  it  would 
have  been  dithcult  for  even  the  most  skilled  diagnostician  to  distinguish 
one  from  the  other. 

]Meyer  ^  injected  Scharlach  oil  into  the  renal  arteries,  under  the  cap- 
sule, and  into  the  parenchyma  of  the  kidney,  in  a  series  of  rabbits  and 
dogs,  but  without  being  able  to  produce  any  effect  upon  the  renal 
epithelium.  In  certain  other  experiments,  in  which  inoculations  had 
been  made  under  the  skin,  he  found  that  when  a  vein  or  an  artery  had 
been  ligated  the  action  of  the  stain  was  hastened,  and  that  under  these 
conditions  even  oil  alone,  or  oil  and  paraffin,  would  inaugurate  epithe- 
lial proHferation.  The  growth  of  epitheHum  in  the  rabbit's  ear  was, 
therefore,  according  to  this  author,  due  to  chronic  inflammation  asso- 
ciated with  other  circulatory  disturbances. 

This  view  was  challenged  by  Greischer,^  who,  working  with 
Schmincke,  induced  anemia  in  one  ear  of  each  of  a  series  of  rabbits  by 
ligating  the  carotid,  arterial  hyperemia  in  others  by  cutting  the  cervical 
sympathetic,  or  finally,  venous  hyperemia  by  the  hgation  of  veins 
at  the  base  of  the  ear.  The  lesions  accompanying  inoculation  of  the 
operated  ear  were  always  the  same  as  those  obtaining  in  the  normal 
one  of  the  opposite  side,  and  epithelial  proliferation  could  never  be  dis- 
covered in  the  prepared  ear  when  it  had  not  occurred  in  the  normal  one. 
Disturbances  of  circulation,  therefore,  played  a  role  only  in  so  far  as 
they  shortened  or  protracted  the  length  of  time  during  which  the 
injected  material  could  act  upon  the  epithelium. 

White  ^  introduced  oleic  acid,  either  pure  or  with  the  addition  of  carbon 
dioxide  or  methyl  oxalate,  into  the  ears  of  rabbits,  the  mammary 
glands  of  guinea-pigs,  and  the  backs  of  mice.  Notwithstanding  the 
fact  that  his  findings  corresponded  so  exactly  with  those  of  Fischer  that, 
as  he  himself  said,  the  illustrations  pubhshed  by  that  author  might 
have  been  prepared  from  his  own  specimens,  White  could  not  find  the 
slightest  evidence  of  any  chemotactic  influence.  Thus,  there  was 
no  intrusion  by  the  epithelium,  and  hair  folHcles  outside  the  inflam- 

1  Beitr.  zur  path.  Anal.,  etc.,  (Ziegler),  1909,  xlvi,  437. 
'^Inaugural  Disserlation,  Miinchen,  1911. 

Miinch.  med.  Woch.,  1911,  Iviii,  1608. 
*  Jour.  Path,  and  Bad.,  1910,  xiv,  450. 


36  ATTEMPTS  TO  PRODUCE  TUMORS 

matory  zone  remained  entirely  unaltered ;  and  although  it  was  true 
that  epithelial  cells  lined  the  abscesses,  this  was  merely  an  expres- 
sion of  the  normal  tendency  of  these  elements  to  grow  over  a  free 
surface  and  could  not  be  attributed  to  any  specific  property  of  the 
fatty  acids  employed.  The  injected  materials  appeared  to  act  merely 
as  chronic  irritants. 

Although  White's  results  were  negative  with  oleic  acid  in  liquid 
paraffin  and  with  a  mixture  of  oleic  acid  and  cholesterin,  a  positive 
action  was  claimed  for  these  substances  by  Wacker  and  Schmincke.^ 

Benthin^  injected  the  ears  of  animals,  usually  rabbits,  with  paraffin, 
oHve  oil,  agar,  agar  with  calcium  carbonate  and  calcium  phosphate, 
Sudan  III,  Scharlach  R,  indophenol,  amidoazobenzol,  paratoluidin, 
amidoazotoluol,  a-naphthylamine,  indol,  skatol,  paraffin  with  soot, 
gum  arable  alone  and  with  Sudan  III,  oleic  acid,  and  glycerine.  No 
growth  was  obtained  after  olive  oil,  agar,  or  gum  arabic  alone,  and 
none  following  agar  with  calcium  carbonate  or  calcium  phosphate, 
while  the  injection  of  parafiin  and  soot  gave  rise  only  to  epithelial  cysts. 
Oleic  acid,  glycerine,  paratoluidin,  and  amidoazobenzol  were  unsuitable, 
for,  as  Stoeber  had  already  pointed  out,  they  caused  too  much  necrosis. 
The  most  marked  growth  accompanied  the  use  of  Sudan  III  and  Schar- 
lach R,  and  Fischer's  statements  regarding  the  action  of  these  dyes  were 
verified  by  Ben  thin,  who,  nevertheless,  did  not  believe  that  the  far-reach- 
ing conclusions  drawn  by  that  author  could  be  justified.  The  growth 
of  epithehal  cells  around  the  oil  droplets  seemed  to  occur  only  when 
there  was  contact  between  the  two,  and  deeply  lying  masses  of  oil, 
even  though  of  considerable  size,  did  not  become  inclosed  by  epithelium. 
The  author  ascribed  the  epithelial  proliferation  to  a  complex  of  causes 
among  which  inflammation,  tissue  tension,  perhaps  circulatory  distur- 
bances, and,  most  important  of  all,  the  presence  of  certain  chemicals, 
were  jointly  responsible.  It  was  noticed  that  wounds  following  opera- 
tive removal  of  the  injected  areas  healed  with  thick  keloid-like  scars 
as  though  the  fat  stains  had  the  property  of  stimulating  growth. 

Wacker  and  Schmincke,^  reviewing  the  various  materials  used  by 
themselves  and  others  to  educe  epithelial  proHferation,  pointed  out 

^  Miinch.  med.  Woch.,  1911,  Iviii,  1607. 

^  Zeitschrift  f.  Krebsforsch.,  1910-1911,  x,  227. 

^  Miinch.  med.  Woch.,  1911,  Iviii,  1607. 


ATTEMPTS  TO  PRODUCE  TUMORS  37 

that  all  which  had  afforded  a  positive  result  had  this  factor  in  common, 
that  they  possessed  the  solubilities  of  Hpoids  —  produced,  that  is,  a 
physical  change  in  the  Hpoid  membrane  of  the  epithelial  cell.  Still, 
a  few  materials  were  unable  to  inaugurate  proliferation,  possessed  of 
this  property  though  they  were.  That  the  stimulating  action  of  the 
various  agents  was  not  primarily  a  chemical  process,  in  the  sense  of  a 
splitting  up  of  the  lipoid  membrane  surrounding  the  cells,  the  authors 
inferred  from  the  following  experiment.  Bergel  ^  having  already  dem- 
onstrated the  presence  of  a  fat-splitting  ferment  in  lymphocytes. 
Wacker  and  his  associate  injected  the  ears  of  rabbits  with  emulsions  of 
rabbit  spleen,  lymph  nodes,  or  pleural  lymphocytic  effusions,  without, 
however,  being  able  to  find  any  evidence  of  the  epithehal  growth  which 
should  have  taken  place  were  lipoidolysis  a  factor  in  its  initiation. 

McConnell  -  tested  the  question  whether  Sudan  III  dissolved  in  oil 
would  exert  any  influence  upon  the  cells  of  an  epithehal  tumor.  Hu- 
man carcinoma  was  suspended  in  sahne  solution  and  injected  into 
SLxteen  white  rats,  of  which  eight  were  subsequently  inoculated  at  the 
same  site  with  three  minims  of  Sudan  oil.  No  growth  took  place 
either  in  the  inoculated  animals  or  in  the  controls. 

Werner^  investigated  the  effect  of  Scharlach  R  upon  growing  mouse 
tumors  and  found  that  concentrated  solutions  in  oil  excited  growth, 
while  alcoholic  solutions  caused  the  tumor  at  first  to  shrink  and  finally 
to  slough  away.  The  excitation  of  growth  caused  by  the  oily  solution 
was  not  the  result  of  chemotactic  influences,  but  of  a  true  growth  stimu- 
lus. 

Powdered  Scharlach  R  was  added  to  tumor  emulsions  before  in- 
oculation by  Albrecht  and  Hecht,^  to  see  whether  the  vigor  of  growth 
would  be  augmented.  In  contrast  to  Werner's  findings  regarding 
tumors  already  established,  the  dye  neither  incited  the  cells  to  increased 
proliferation  nor  did  it  inhibit  their  growth. 

A  review  of  certain  aspects  of  the  more  recent  attempts  to  estabHsh 
mahgnant   growth  has  been  pubhshed  by  Herxheimer  and  Reinke.^ 

^  Miinch.  med.  Woch.,  1909,  Ivi,  64. 

Miinch.  tJted.  Woch.,  1910,  Ivii,  1683. 
^  Jour.  Med.  Research,  1908,  N.S.,  xiii,  381. 
^  Munch,  med.  Woch.,  1908,  Iv,  2267. 
*  Cenfralbl.  f.  allg.  Path.,  etc.,  1909,  xx,  1039. 
^  Ergebnisse  der  dig.  Path.,  etc.  (Lubarsch  and  Ostertag),  Abt.  ii,  1909,  xiii,  416. 


38  ATTEMPTS  TO  PRODUCE  TUMORS 

The  effect  of  ether  upon  the  cells  of  the  salamander,  discovered  by 
Reinke,  corresponded  entirely  with  experiments  in  plants  where  it 
had  been  found  that  hibernation  could  be  overcome  with  ether,  and 
premature  blossoming  brought  about.  It  was  further  parallel  with 
hemolysis,  which  was  due  to  solution  of  the  lipoids  of  red  blood  cells, 
and  Reinke  had  therefore  suggested  that  blastosis,  or  stimulation  to 
mitotic  cell  division,  might  perhaps  be  interpreted  as  the  final  outcome 
of  a  melting,  saponification,  or  solution  of  hpoids  in  the  cells  and 
their  nuclei,  taking  place  in  the  same  way  as  in  hemolysis.  The  sug- 
gestion was  strengthened  by  Askanazy's  observation  of  the  increased 
growth  power  of  embryo  rat  tissue  after  exposure  to  ether.  Somewhat 
later,  and  independently  of  Reinke,  J.  Loeb  had  reached  similar  con- 
clusions, deciding  that  it  was  the  fat-dissolving  properties  of  the 
substances  with  which  he  was  working  that  enabled  him  to  achieve 
artificial  parthenogenesis.  Furthermore,  Scharlach  oil  and  the  afhhated 
substances  that  had  been  utihzed  by  Fischer  and  his  successors  were 
also  solvents  of  Hpoids,  a  circumstance  that  could  be  correlated  with 
Overton's  theory  of  a  hpoid  ectoplasm.  Although  any  serious  injury 
to  the  cell  was  followed  by  cytolysis,  as  could  be  demonstrated  most 
easily  through  the  appHcation  of  heat,  if  the  action  of  this  agent  were 
not  so  intense  as  to  lead  to  destruction  the  protoplasm  became  more 
active,  metaboHsm  was  increased,  ferments  were  set  working,  and  latent 
vital  processes  were  awakened.  Ether  caused  a  change  in  the  condition 
of  those  important  elements,  the  lipoids,  whose  role  in  cell  division 
could  be  readily  harmonized  with  Weigert's  conception  of  proKferation, 
according  to  which  tissue  injury  was  interpolated  between  interference 
with  the  cell  and  subsequent  growth.  Herxheimer  and  Reinke  could 
see  no  reason,  therefore,  to  abandon  Weigert's  view  that  there  could  be 
no  direct  stimulation  of  cell  growth,  and  it  seemed  justifiable  to  ac- 
cept with  him  the  existence  of  an  external  functional  stimulus,  but  to 
refer  growth  to  a  preceding  injury. 


CHAPTER   III 

EARLIER  OBSERVATIONS  ON  THE  TRANSMISSIBILITY  OF  CANCER 

Long  before  it  was  realized  that  the  question  of  the  transmissibility 
of  cancer  could  be  approached  through  experiment  upon  the  lower 
animals,  its  solution  had  been  attempted  by  means  of  the  much  less 
exact  method  of  cUnical  observation ;  and  although  numerous  in- 
stances of  transfer  of  the  disease  have  been  recorded,  most  of  them  so 
seriously  exceed  the  limits  of  creduHty  that  the  occurrence  of  cancer 
in  the  two  patients  may  be  attributed  to  chance. 

Butlin^  has  laid  down  with  admirable  clearness  certain  conditions 
which  reasonably  may  be  demanded  before  it  is  agreed  that  any  given 
case  illustrates  the  transmission  of  malignant  disease  from  one  person 
to  another.  " .  .  .  all  cases  of  reported  contagion  of  cancer  in  which 
the  disease  is  not  of  the  same  variety  must  be  unhesitatingly  rejected ; 
.  .  .  cases  must  not  be  accepted  where  there  is  no  evidence  that  the 
affected  parts  of  the  two  individuals  were  from  time  to  time  in  con- 
tact; ...  it  is  extremely  improbable  that  contagion  should  take 
place  from  a  covered  cancer,  such,  for  instance,  as  a  cancer  buried  in  the 
breast ;  or  that  the  disease  could  be  implanted  in  a  part  the  covering 
of  which  has  not  been  broken." 

.  A  few  cases  of  the  reputed  transmission  of  cancer  may  now  be 
examined  to  see  in  how  far  they  conform  to  Butlin's  requirements. 

TRANSFER  FROM   ONE   PERSON   TO   ANOTHER 

Accidental 

Zacutus  -  reported  the  following  case,  perhaps  the  first  to  appear 
in  the  literature.  "A  poor  woman  who  had  suffered  for  many  years 
from  an  ulcerated  cancer  of  the  breast,  slept  at  night  on  the  same 

-  ^  British  Med.  Jour.,  1907,  ii,  255. 
-  Praxis  MedicaAdmiranda,  p.  3i,obs.  124  (Appendix  to  Opera,  tome  ii,  Lugduni,  1649). 

39 


40      E.IRLIER    OBSERVATIONS    ON    THE    TRANSMISSIBILITY    OF    CANCER 

couch  with  her  three  sons.  All  three  became  affected  with  a  like 
disease.  Five  years  after  the  death  of  the  mother,  two  of  the  sons 
died ;  but  the  third,  being  more  robust,  recovered  with  difficulty 
after  having  submitted  to  excision  of  the  cancer  at  the  hands  of  a 
surgeon." 

Tulpius  ^  expressed  surprise  that  there  should  exist  any  doubt  as 
to  the  contagiousness  of  ulcerating  cancer,  and  related  a  case  that 
had  come  within  his  own  experience.  "Adriana  Lambert,  a  woman 
advanced  in  years,  was  afflicted  with  a  cancer  of  the  breast  that  had 
advanced  to  such  a  putrid  condition  as  to  infect  by  its  exhalations 
her  body-servant  who  attended  upon  her,  living  in  close  contact  with 
the  mistress.  Some  evil  spark  lighted  such  a  conflagration  as  to 
destroy  the  maid  no  less  than  her  mistress,  for  such  a  foul,  irregular 
ulcer  invaded  the  breast  and  armpit  of  each  that  I  am  undecided  which 
of  these  two  was  tortured  with  the  greater  savagery." 

Juncker  -  believed  that  cancer  was  contagious,  but  not  virulently  so 
unless  it  were  implanted  in  situations  suitable  for  its  reception,  and 
especially  in  a  place  where  solution  of  continuity  of  the  tissues  had 
been  effected. 

That  there  existed  in  Juncker's  day  a  popular  belief  in  the  con- 
tagiousness of  cancer  is  shown  by  an  episode  which  Guelliot  ^  has 
reported.  Cancer  patients  having  been  refused  admission  at  the 
Hotel  Dieu  in  Reims,  Jean  Godinot,  a  canon  celebrated  for  his  charity, 
offered  the  sum  of  twenty-five  thousand  livres  for  the  construction  of 
a  hospital  for  such  patients,  who  until  then  had  been  able  to  subsist 
only  through  what  they  could  gain  from  compassionate  worshippers 
by  exposing  their  sores  at  the  church  door.  A  house  was  bought  in 
the  center  of  the  town  and  opened  as  the  Hopital  Saint-Louis,  and 
here  cancer  patients  were  cared  for,  but  on  condition  that  they  were 
not  to  leave  the  building.  The  neighbors,  however,  complained  that, 
as  cancer  was  contagious,  the  health  of  the  public  would  be  endangered 
if  such  an  estabhshment  were  tolerated  in  a  populous  quarter,  and  the 
administration  was  finally  compelled  to  transport  its  charges  to  a 
lazaret  formerly  used  for  idctims  of  the  pest.     It  was  not  until  1841 

^  Observationes  Medicae,  Amstelredami,  1672,  editio  nova,  292. 
^  Conspectus  Chirurgiae  tarn  Medicae,  Halle,  1721,   327, 
^  Gaz.  des  Hopit.,  1892,  Ixv,  1210. 


EARLIER    OBSERVATIONS    ON   THE    TRANSMISSIBILITY    OF    CANCER      4 1 

that  cancer  cases  were  admitted  to  a  general  hospital,  and  even  then 
they  were  kept  in  a  separate  ward. 

Viel-Hautmesnil  ^  reported  the  three  following  cases  as  apparent 
instances  of  the  transmission  of  cancer.  Mr.  Smith,  of  St.  Thomas's 
Hospital  in  London,  tasted  the  contents  of  a  small  cyst  in  a  mammary 
cancer  which  he  had  just  removed.  The  acrid  taste  remained  per- 
manently in  his  mouth,  and  he  became  subject  to  attacks  of  vomiting 
which  ultimately  determined  his  death.  A  doctor  was  said  to  have 
died  of  cancer  which  had  apparently  been  communicated  to  him  by 
his  wife.  The  third  example  was  a  case  reported  by  Tulpius,  con- 
cerning a  surgeon  whose  wife  suffered  from  mammary  cancer.  Ac- 
customed to  apply  his  mouth  and  tongue  to  the  affected  part  in  order 
to  relieve  the  intense  pain,  he  soon  afterward  died  of  a  terrible  cancer 
which  destroyed  the  interior  of  his  mouth. 

The  foregoing  cases  of  transference  are  interesting,  of  course,  only 
in  so  far  as  they  show  the  age  of  the  question  now  under  discussion, 
for  before  the  time  when  the  microscope  had  come  into  general  use 
the  diagnosis  of  cancer  was  often  so  highly  problematical  that  reports 
of  transmission  of  the  disease  may  be  dismissed  with  scant  curtesy. 
Still,  even  after  the  importance  of  histological  diagnosis  had  been  es- 
tabhshed,  examples  of  contagion  continued  to  be  described,  most  of 
them,  however,  on  a  par  with  the  earlier  instances  through  the  neglect 
of  the  observers  to  advance  adequate  microscopic  justification  for 
their  claims. 

Budd  -  has  related  the  case  of  a  strong  and  healthy  girl  of  nineteen 
who  regularly  washed  dressings  and  linen  soaked  with  the  discharge 
from  an  advanced  case  of  uterine  and  vaginal  cancer.  Six  months 
after  the  death  of  the  patient  the  young  woman  was  admitted  to  the 
hospital  with  a  large  axillary  cancer,  which  eventually  proved  fatal. 
Budd  noted,  further,  that  five  surgeons  of  the  same  institution  had 
died  of  cancer  within  a  few  years,  and  expressed  the  opinion  that  such 
a  mortality  could  hardly  be  conceived  except  on  the  supposition  that 
the  disease  had  been  communicated,  at  least  to  some  of  them,  during 
manipulations  on  patients  sufifering  from  cancer. 

Whitehead  ^  had  under  his  care  a  man  with  an  extensive  epithe- 

1  Consid.  gen.  medico-chir .  sur  le  Cancer;  These  de  Paris,  1807,  24. 
^  Lancet,  1887,  ii,  1091.  ^  Lancet,  1887,  ii,  1040. 


42       EARLIER    OBSERVATIONS    ON   THE    TRANSMISSIBILITY    OF    CANCER 

lioma  of  the  lower  lip,  attributed  by  the  patient  to  his  habit  of 
drinking  daily  out  of  a  small  vessel  used  by  his  father,  who  had  died 
during  the  previous  year  of  the  same  disease. 

Adam  ^  described  the  case  of  a  medical  man  who  married  a  woman 
subsequently  found  to  be  the  victim  of  mammary  and  uterine  cancer, 
from  which  she  soon  afterward  died.  Within  a  short  time  the  widower 
had  developed  cancer  of  the  liver  and  stomach,  but  before  his  death 
he  married  again,  and  a  year  or  two  afterward'  it  was  discovered  that 
his  widow  was  the  subject  of  cancer  of  the  breast. 

Smith  ^  reported  a  woman  with  sloughing  carcinoma  of  the  mamma, 
whose  husband  was  attacked  by  cancer  of  the  stomach,  and  Behla  ^ 
collected  fourteen  examples  of  contagion  which  had  occurred  among 
patients  under  his  own  observation.  The  first  in  the  series  was  a 
man  of  seventy-six  who  died  of  carcinoma  of  the  kidney  three  years 
after  his  wife  had  died  of  cancer  of  the  liver.  The  other  thirteen 
instances  were  similar.  To  these  cases  of  cancer  a  deux,  Behla  added 
one  of  cancer  a  trois  which  had  been  communicated  to  him  by  Elsler. 
Herr  B,  who  died  of  carcinoma  of  the  rectum,  was  nursed  by  his 
son-in-law  who  for  six  months  administered  daily  nutrient  enemata. 
A  short  time  after  the  death  of  the  patient  the  son-in-law  developed 
a  carcinoma  of  the  lip,  and  during  his  illness  a  cancer  of  the  breast 
was  discovered  in  his  wife. 

The  following  examples  of  "  cancer  houses  "  have  been  drawn  frorn 
Behla's  monograph.^ 

In  the  village  of  Breitenbach,  with  a  population  of  four  hundred  and 
fifty,  four  persons  died  of  cancer  in  1906,  among  them  a  man  with  a  can- 
cer of  the  lip  who  lived  in  the  house  where  a  man  had  died  of  carcinoma 
of  the  esophagus  in  1905.  A  citizen  of  Rehfeld  died  of  cancer  of  the 
stomach,  and  the  man  to  whom  the  house  was  sold  selected  for  his  living 
room  the  one  in  which  the  previous  owner  had  died,  erecting  his  bed  in 
the  place  where  that  of  his  predecessor  had  formerly  stood.  Although 
he  had  been  in  perfect  health  before  moving  into  this  house,  the  new 
tenant  died  after  about  a. year  from  carcinoma  of  the  stomach. 

^Lancet,  1887,  ii,  766. 

2  Med.  Record,  1895,  xlviii,  383. 

^  Deut.  med.  Woch.,  1901,  xxvii,  427. 

^  Die  Bestdtigung  d.  kunstlichen  Zuchtung  des  Krebserregers,  Berlin,  1910,  ly. 


EARLIER   OBSERVATIONS    ON    THE    TRANSMISSIBILITY    OF    CANCER      43 

Newsholme  ^  has  criticized  the  usual  pubhshed  accounts  of  cancer 
houses  on  the  score  that  the  writers  always  forgot  that  they  were 
deahng  with  small  figures ;  they  forget,  for  instance,  that  if  a  number 
of  persons  were  set  to  tossing  coins,  it  would  happen  eventually  that 
one  of  them  would  toss  a  thousand  heads  without  a  break.  One  who 
remembered  the  occurrence  of  such  coincidences  as  this  would  attach 
little  importance  to  numbers  of  cases  in  particular  houses. 

The  same  idea  has  been  expressed  also  by  Adami,-  who  said : 
^'.  .  .by  the  law  of  chance,  just  as  one  individual  in  a  thousand 
may  be  of  gigantic  proportions,  so  one  house  in  a  thousand  may  show 
a  great  excess  of  cases  of  cancer  —  or  of  twin  births  —  over  the  or- 
dinary run  of  houses." 

Experimental 

Although  the  attempt  has  been  made  to  decide,  by  means  of  ex- 
perimental inoculation,  the  question  regarding  the  transmission  of 
tumors  from  one  person  to  another,  the  number  of  these  experi- 
ments is  so  small  that  no  deduction  can  with  any  safety  be  drawn  from 
them. 

On  October  17,  1808,  at  the  Hopital  de  St.  Louis,  and  in  the  pres- 
ence of  several  physicians  and  students,  Alibert  ^  allowed  himself  to 
be  injected  with  ichorous  material  from  a  cancer  of  the  breast.  The 
experiment  was  performed  at  the  same  time  upon  M.  Fayet,  a  medi- 
cal student,  and  the  next  morning  upon  MM.  Lenoble  and  Durand. 
Except  for  an  inflammatory  reaction  the  experiment  was  without 
sequelcB.  A  week  later  Alibert  inoculated  himself  a  second  time,  and 
his  colleague,  M.  Biett.  He  himself  escaped  with  a  result  similar  to 
that  which  followed  the  first  trial,  but  M.  Biett  developed  a  somewhat 
more  severe  infection,  which  involved  the  axillary  and  cervical  lymph 
nodes. 

Senn  ^  transplanted  into  himself  a  fragment  of  lymph  node  in 
which  carcinomatous  invasion  had  been  demonstrated  by  the  mi- 
croscope. Although  a  nodule  the  size  of  a  pea  appeared  at  the  implan- 
tation site  and  remained  stationary  for  two  weeks,  it  vanished  soon 

^  Trans.  Epidemiological  Sac.  London,  1906-1907,  N.S.,  xxvi,  73. 

^  Principles  of  Pathology,  Philadelphia  and  New  York,  igio,  Vol.  i,  839. 

'  Description  des  Maladies  de  la  Peaii,  Paris,  1825,    118. 

*  Jour.  American  Med.  Assoc,  1901,  xxxvii,  811. 


44       E.4RLIER    OBSERVATIONS    ON    THE    TRANSMISSIBILITY    OF    CANCER 

afterward,  and  seven  weeks  later  a  red  linear  scar  was  the  only  indica- 
tion of  the  experiment. 

Lanz  ^  inoculated  his  gardener  on  the  back  of  the  hand  with  finely 
minced  common  warts  (verruca  vulgaris)  removed  from  another  persons- 
arranging  the  series  in  the  shape  of  the  letter  "J."  The  first  sign  of 
growth  did  not  appear  until  fully  one  and  a  half  months  had  elapsed, 
when  two  or  three  very  small  nodules  were  recognizable.  Two  months 
after  implantation  there  were  eight  warts  forming  a  "J  "  and  each 
about  the  size  of  a  pinhead,  while  a  month  later  the  number  had  in- 
creased to  twelve.  Lanz  said,  further,  that  as  a  result  of  rubbing  down 
the  warts  of  a  patient,  he  himself  had  acquired  several  of  these 
tumors. 

TRANSPLANTATION  OF  TUMORS  INTO  THEIR  BEARERS 

Accidental 

Although  it  may  be  true  that  tumors  can  be  transplanted  by  con- 
tact under  certain  conditions,  not  a  few  of  the  instances  that  have  been 
reported  to  illustrate  this  type  of  implantation  may  have  been  cases 
either  of  multiple  tumors  or  of  retrograde  metastasis ;  and  the  amount 
of  care  which  is  necessary  to  eliminate  error  is  well  shown  in  an  article 
by  Petersen.^  In  a  case  of  inoperable  carcinoma  of  the  uterus,  the 
skin  in  the  neighborhood  of  the  vulva  contained  a  number  of  small 
nodules  and  a  few  indurated  ulcers  which  seemed  clearly  enough  to 
be  the  outcome  of  auto-inoculation.  Examination  of  serial  sections, 
however,  proved  definitely  that  they  were  the  result  of  retrograde 
lymphatic  metastasis. 

Full  as  the  Hterature  is  of  examples  of  reputed  transfer  by  contact, 
there  are  but  few  which  satisfy  Ewing's  demand  ^  that  "...  the 
transferred  tumor  shall  exhibit  a  structure  similar  to  that  of  the  orig- 
inal, but  different  from  that  spontaneously  arising  in  the  invaded 
tissue." 

A  useful  set  of  standards  for  the  guidance  of  those  engaged  in  the 
critical  study  of  these  cases  has  been  formulated  by  ButHn  ^  as  follows  : 
"The  disease  must  be  of  the  same  variety  in  the  primary  carcinoma 

1  Dent.  med.  Woch.,  1899,  xxv,  313.  2  ^^.^/^  y  Dermat,  u.  Syph.,  1904,  Ixx,  313. 

3  Arch.  Internal  Med.,  1908,  i,  177.  ^  British  Med.  Jour.,  1907,  ii,  256. 


EARLIER    OBSERVATIONS    ON    THE    TRANSMISSIBILITY    OF    CANCER      45 

and  in  the  reputed  contact-cancer.  The  identity  of  the  disease  must 
be  proved  by  microscopical  examination.  The  primary  disease  must 
have  been  exposed  at  the  time  at  which  the  contact  is  known  to  have 
taken  place ;  and  there  should  be  such  evidence  of  contact  of  the  pri- 
mary carcinoma  with  the  seat  of  the  reputed  contact-cancer  as  would 
satisfy  a  jury." 

The  necessity  for  microscopical  control  was  illustrated  by  an  anec- 
dote. A  specimen  that  had  been  exhibited  as  an  example  of  contact 
transfer  having  been  finally  cut  and  examined,  it  was  found  that  an 
ulcer  on  the  cheek  immediately  opposite  a  carcinoma  of  the  gum  was  a 
simple  inflammatory  lesion. 

Klebs  ^  described  three  instances  of  squamous  cell  epithelioma  of 
the  stomach,  two  of  which  were,  in  his  opinion,  undoubtedly  due  to 
infection  of  the  mucous  membrane  by  particles  implanted  on  it, 
while  the  third  had  probably  been  so  produced.  The  primary  tumors 
involved  respectively  the  esophagus,  the  face,  mouth,  and  throat, 
and    the    tongue. 

Kaufmann  ^  recorded  the  case  of  a  woman  with  an  ulcerating  epi- 
theHoma  on  the  dorsal  surface  of  the  right  hand,  who  was  in  the  habit 
of  rubbing  her  eye  with  the  back  of  the  afifected  member.  About 
three  years  after  the  discovery  of  the  tumor  a  small  ulcerating  growth 
developed  on  the  inner  side  of  the  right  lower  lid.  Both  ulcers  had 
all  the  microscopic  characteristics  of  a  cancroid. 

Kraske  ^  had  seen  two  patients  with  primary  cylindrical  cell  car- 
cinoma situated  high  up  in  the  rectum,  who  had  developed  similar 
growths  close  to  the  anus  and  separated  by  a  considerable  distance 
of  healthy  tissue  from  the  higher  tumor.  The  lowermost  were  in 
the  region  normally  covered  by  squamous  epithehum,  a  circumstance 
which  seemed  to  exclude  the  possibility  of  their  having  been  primary, 

V.  Bergmann  ^  discussed  a  patient  with  an  ulcerating  epithe- 
lioma on  the  lower  lip  and  a  tumor  of  the  same  type  on  the  upper 
at  a  precisely  corresponding  point.  The  former  growth  had  appeared 
three  months  before  the  man  came  under  observation  and  the  latter 
six  or  seven  weeks  later,  but  not  until  after  the  lower  tumor  had  ul- 

^  Handbuch  d.  path.  AnaL,  Berlin,  1868,  Bd.  i,  erste  Abt.,  190. 

"^  Arch.  f.  path.  Anat.,  etc.,  (Virchow),  1879,  Ixxv,  317. 

'  Centralbl.f.  Chir.,  1884,  xi,  801.  '^  Berl.  klin.  Woch.,  1887,  xxiv,  891. 


46      EARLIER   OBSERVATIONS    ON    THE    TRANSMISSIBILITY    OF    CANCER 

cerated.  In  answer  to  an  inquiry  from  Butlin^  the  author  replied 
that  the  growths  had  been  subjected  to  microscopical  examination 
and  found  to  be  epitheliomata. 

A  woman  under  the  observation  of  Hamburger  ^  was  admitted  to 
hospital  with  an  epithelioma  of  the  left  labium  minus  about  the  size 
of  a  hen's  egg,  first  noticed  two  years  before.  On  admission  there 
was  discovered  at  a  corresponding  point  on  the  right  labium  minus 
a  small,  raised,  ulcerating  tumor  which  the  history  stated  was  of 
only  two  months'  duration.  Microscopical  examination  proved  that 
both  growths  were  squamous  cell  epitheliomata. 

Thorn  ^  found  a  carcinoma  of  the  cervix  uteri  coupled  with  a  car- 
cinomatous ulcer  in  the  left  side  of  the  vagina,  but  without  involve- 
ment of  the  fornix.  Perimetritic  adhesions  had  drawn  the  uterus  to 
the  right,  tilting  an  exceptionally  long  cervix  to  the  left  so  that  the  cer- 
vical lesion  had  been  kept  in  constant  contact  with  the  left  vaginal  wall. 
Both  tumors  presented  the  same  histological  structure.  In  a  second 
case,  a  carcinoma  involved  both  right  labia  and  a  shallow  carcinoma- 
tous ulcer  occupied  a  corresponding  point  on  the  left  side,  although  the 
tissues  intervening  had  remained  intact.  No  statement  was  made 
regarding  the  structure  of  the  tumors  in  the  latter  case. 

Butlin  ^  collected  two  cases  in  which  an  epithelioma  had  arisen  on 
one  labium  at  the  exact  place  of  contact  with  a  similar  tumor  on  the 
other  side,  and  one  where  a  labial  tumor  opposite  to  an  epithelioma 
was  not  malignant.  He  further  reported  three  examples  of  apparent 
transfer  from  one  side  of  the  larynx  to  the  other,  and  a  fourth  instance 
in  which  an  ulcer  of  one  vocal  cord  immediately  opposite  to  an  epi- 
thelioma on  the  other  was  demonstrated  by  microscopical  examination 
to  be  merely  an  inflammatory  lesion.  Among  various  examples  re- 
garding other  parts  of  the  body,  there  was  described  an  ulcerated 
epithelioma  of  the  lower  Hp  in  a  patient  who  had  the  habit  of  pressing 
his  forefinger  against  the  ulcer  and  then  rubbing  it  on  his  nose. 
Twenty  months  after  the  excision  of  the  tumor  the  patient  presented  a 
large  ulcerated  patch  on  the  nose.  This  lesion,  first  noticed  three 
months  after  the  operation  on  the  lip,  was  proved  by  the  microscope 
to  be  of  identical  structure  with  the  first  tumor. 

^  British  Med.  Jour.,  1907,  ii,  259.  2  Hospilahtidende,  1892,  x,  81. 

^  Ceniralbl.  f.  Gyndkol.,  1894,  xviii,  228.  '^British  Med.  Jour.,  1907,  ii,  257. 


EARLIER    OBSERVATIONS    ON    TKE    TRANSMISSIBILITY    OF    CANCER      47 

Secondary  growths  of  the  Fallopian  tube  arising  by  implantation 
of  cells  from  malignant  tumors  in  the  abdominal  organs  have  been 
described  by  many  authors,  one  of  the  most  recent  being  Wakasugi.^ 
The  nodules  are  found  on  the  outer  aspect  of  the  tube,  or,  as  occurs 
not  infrequently  in  the  case  of  ovarian  carcinoma,  in  the  mucous 
membrane. 

It  has  often  been  observed  that  particles  of  tumor,  eluding 
the  vigilance  of  the  surgeon  at  operation,  have  been  spread  through 
the  wound  to  demonstrate  later  in  the  most  unhappy  way  the  possi- 
bility of  ingrafting  a  tumor  into  the  indi\ddual  in  whom  it  has  orig- 
inated. 

Thus  Quincke  -  recorded  a  case  of  peritoneal  carcinosis  in  which, 
as  the  result  of  abdominal  puncture  for  ascites,  there  was  found  in 
the  subcutaneous  tissue  at  autopsy  a  carcinoma  identical  in  structure 
with  the  peritoneal  nodules,  although  the  intervening  tissues  were 
free  from  growth.  The  secondary  tumor  had  been  clinically  recog- 
nizable as  early  as  the  tenth  day  after  puncture. 

Thorn  ^  saw  a  patient  who  had  submitted  two  years  pre^'iously  to 
vaginal  hysterectomy,  during  which  lateral  incisions  had  been  made  to 
overcome  the  narrowness  of  the  vaginal  orifice.  Renewed  hemor- 
rhage necessitating  subsequent  examination,  a  small  recurrence  was 
discovered  in  the  scar,  and  upon  microscopical  examination  it  was 
shown  that  this  nodule  exactly  resembled  the  original  carcinoma  of 
the  cervix.  A  second  and  similar  instance  of  implantation  was  de- 
scribed  by   the   same   author. 

Lack  ^  discussed  two  cases  in  which  the  rupture  of  a  carcinomatous 
lymph  node  during  operation  was  followed  by  recurrence  in  the  scar, 
a  third  where  recurrence  supervened  at  the  site  of  a  tracheotomy 
wound  after  excision  of  a  sarcoma  of  the  lower  jaw,  and  two  examples 
of  apparent  implantation  in  tracheal  wounds  during  operation  for 
cancer  of  the  larynx. 

Richardson  '^  reported  a  patient  wdth  carcinoma  of  the  breast  in 
whom  an  exploratory  puncture  had  been  performed  four  weeks  previ- 

^  Beitr.  zur.  path.  Anat.,  etc.  (Ziegler),  1910,  xlvii,  483. 

^  DeuL  Arch.  f.  klin.  Med.,  1875,  ^vi,  134. 

^  Centralbl.  f.  Gyndkol.,  1894,  xviii,  228.  ^Lancet,  1896,  i,  1638. 

^  Boston  Med.  and  Surg.  Jour.,  1898,  cxxix,  414. 


48       EARLIER    OBSERVATIONS    OX    THE    TR.\XSMISSIBILITY    OF    CAXCER 

oush'.  At  operation  a  small  nodule  was  found  in  the  pectoralis 
minor,  and  the  entire  mass  was  therefore  thoroughly  removed.  ''The 
examination  of  the  tumor  and  the  pectoralis  major  showed  a  clear 
space  between  the  two.  A  nodule  was  found  among  the  fibers  of  the 
pectorahs  major  corresponding  in  position  and  size  to  that  in  the 
pectoralis  minor,  and  in  the  same  general  line  ^^dth  the  two  just  de- 
scribed there  was  a  stellate  maHgnant  mass  in  the  axillary  fat,  not 
connected  mth  the  enlarged  lymph  nodes. 

"  The  infection  of  the  pectorahs  major,  the  pectorahs  minor,  and  the 
axilla,  in  a  straight  line,  shows,  I  think,  a  direct  contamination  of  pre- 
viously healthy  parts  by  the  exploring  punch,  for  the  nodules  were  of 
about  the  same  size  and  age,  and  in  the  muscles,  at  least,  they  were 
the  only  ones  found."  Discussing  the  transplantation  of  tumors  into 
their  bearers,  Richardson  added  that  he  had  seen  the  "...  stitch- 
holes  of  a  closed  abdominal  wound,  after  nephrectomy  for  sarcoma  of 
the  kidney,  burst  out  with  luxuriant  masses  of  recurrent  disease." 

Experimental 

The  problem  whether  or  not  a  tumor  can  be  transplanted  success- 
fully into  its  bearer  has  even  been  subjected  to  experimental  investi- 
gation, although,  as  E^^'ing  ^  has  said:  "Xo  experimental  e\ddence  is 
needed  to  show  that  a  mahgnant  tumor  may  often  be  grafted  froni 
one  part  of  the  patient's  body  to  another,  since  the  several  recognized 
modes  of  metastasis  daily  demonstrate  this  process." 

Hahn  -  seems  to  have  been  the  first  to  approach  this  question  from 
the  experimental  standpoint.  In  a  case  of  inoperable  recurrence  of 
a  marmnary  carcinoma,  three  portions  of  infiltrated  skin  were  trans- 
planted into  the  sound  integument  overlying  the  normal  breast  on 
the  opposite  side.  About  eleven  weeks  after  the  operation  all  three 
grafts  had  developed  into  nodules  which  were  demonstrated  by 
the  microscope  to  be  carcinomata.  Mrchow  ^  objected,  however, 
that  this  experiment  did  not  demonstrate  the  transplantation  of  a 
tumor  into  its  bearer,  because,  as  the  entire  skin  had  been  transferred, 

1  Arch.  Internal  Med.,  1908,  i,  176. 

2  Berl.  klin.  Woch.,  1887,  xxiv,  892. 

BerL  klin.  Woch.,  1888,  xxv,  413.     See  also  Frank,  Dent.  med.  Woch.,  1891,  r\ii,  933. 
^  Berl.  klin.  Woch.,  1887,  xxiv,  892. 


EARLIER   OBSER\'ATIOXS    ON    THE    TRANSMISSIBILITY    OP    CANCER      49 

the  tumor  had  grown  in  its  new  location  only  in  so  far  as  it  was  situ- 
ated in  the  implanted  integument.  The  case,  therefore,  was  entirely 
analogous  to  the  ingrafting  of  a  portion  of  skin  containing  hair,  which, 
even  though  successful,  could  not  be  held  to  have  demonstrated  the 
transplantabihty  of  hair. 

Senn  ^  transferred  a  fragment  of  epithelioma  to  the  subcutaneous 
tissue  of  the  patient's  leg,  but  nothing  remained  of  the  graft  after 
the  expiration  of  four  weeks. 

Cornil  -  reported  two  cases  of  the  inoculation  of  a  tumor  into  its 
bearer,  by  a  surgeon  whose  name  was  withheld.  In  the  first  instance 
a  graft  from  a  spindle  cell  sarcoma  of  the  mamma,  inserted  into  the 
normal  breast  on  the  other  side,  had  reached  the  size  of  an  almond  at 
the  end  of  two  months.  This  nodule,  when  removed  and  subjected 
to  microscopical  examination,  proved  to  be  a  spindle  cell  sarcoma 
similar  to  the  primary'  tumor.  The  patient  died  somewhat  later  of 
an  intercurrent  disease,  but  no  secondary  tumors  were  demonstrable 
at  autopsy  in  spite  of  the  most  painstaking  search.  The  second  case 
was  similar  except  that  the  implanted  growth  was  an  adeno-carcinoma. 
The  secondary  nodule,  while  it  had  all  the  clinical  characteristics  of 
a  new  growth,  was  not  removed,  on  account  of  the  patient's  reluctance 
to  submit  to  another  operation,  and  microscopical  proof  of  its  nature 
could  not,  therefore,  be  advanced. 

Thorn  ^  wrote  that  in  six  cases  of  inoperable  carcinoma  of  the  uterus 
he  had  made  about  twenty  implantations  in  the  respective  patients, 
either  by  se^\'ing  small  pieces  of  growth  into  the  mucous  membrane 
of  the  vagina  or  by  rubbing  fragments  into  small  vaginal  wounds. 
Although  one  of  these  grafts  seemed  to  proHferate  for  three  weeks  it 
disappeared  soon  afterward,  and  the  outcome  in  all  the  other  experi- 
ments had  been  negative. 

To  the  subject  of  implantation  cancer  as  a  whole  Milner  ^  has  con- 
tributed an  exhaustive  critical  review  which  includes  two  hundred 
references. 

1  Surgical  Bacteriology,  Philadelphia,  1889,  261. 
^  Semaine  med.,  1891,  xi,  259. 

Bull,  de  I'Acad.  de  Med.,  1891,  xxv,  906. 
^  Centralbl.  f.  Gyndkol.,  1894,  xviii,  228. 
^Arch.f.  klin.  Chir.,  (v.  Langenbeck),  1904,  Lxxiv,  669,  1009. 


50      EARLIER    OBSERVATIONS    ON    THE    TRANSMISSIBILITY    OF    CANCER 
ATTEMPTS    TO    TRANSFER  HUMAN   TUMORS    TO   ANIMALS 

Since  the  day  when  Peyrilhe  ^  made  the  first  recorded  experiment, 
attempts  to  transfer  cancer  from  man  to  the  lower  animals  have  been 
almost  continuously  in  progress,  and  although  a  positive  result  has 
been  reported  more  than  once,  the  consensus  of  opinion  has  been  for 
many  years  that  such  claims  cannot  be  seriously  entertained. 

Peyrilhe's  account  of  his  investigation  appears  in  the  English  trans- 
lation of  the  Dissertation  in  the  following  words :  "I  will  relate  here 
an  experiment  which  I  myself  made  with  the  cancerous  virus. 
I  procured  about  two  drachms  of  it  from  a  cancerous  breast,  and 
introduced  it  by  means  of  a  syringe,  into  a  small  wound  made  in  the 
back  of  a  .dog.  I  covered  the  wound  with  a  plaster  and  bandage, 
and  in  three  days  removed  the  dressing ;  the  retraction  of  the  skin 
afforded  an  ulcer,  which  already  afforded  a  very  disagreeable  smell : 
it  was  of  a  dark  violet  color,  and  the  parts  all  around  it  were  emphy- 
sematous. I  covered  it  again  with  the  same  plaster,  and  in  forty- 
eight  hours  opened  it  again  for  the  second  time.  The  effects  were 
then  more  violent.  The  whole  skin  from,  the  head  to  the  tail  was 
completely  emphysematous.  A  little  ichorous  blackish  matter  flowed 
from  the  wound.  The  eyes  of  the  animal  were  vivid,  and  he  seemed 
to  have  a  great  thirst :  in  this  state  the  poor  creature  was  perpetually 
howling.  At  length  my  maid,  disgusted  by  the  stench  of  the  ulcer, 
and  softened  by  the  cries  of  the  animal,  put  an  end  to  his  life,  and  thus 
prevented  my  observing  the  ultimate  effects  of  this  disease." 

Dupuytren  ^  fed  animals  with  cancerous  material,  introduced  it 
into  the  abdomen,  injected  cancer  juice  into  the  peritoneal  cavity  and 
the  veins,  and  inoculated  the  pus  of  an  ulcerated  cancer,  but  without 
succeeding  in  transmitting  the  disease. 

Langenbeck  ^  injected  into  the  femoral  vein  of  a  dog  the  juice  from 
a  medullary  carcinoma  of  the  humerus,  mixed  with  the  dog's  own 
serum,  and  two  months  afterward,  when  the  animal  was  autopsied, 

1  Disscrtatio  Academica  de  Cancro,  Antverpiae,  1775. 
A  Dissertation  on  Cancerotis  Disease,  London,  1775. 

2  Cited  by  Viel-Hautmesnil,  Considerations  generales  medico-chirurgicales  sur  le  Cancer, 
Paris,  1807,    23. 

^  Schtnidt's  Jahrbticher,  1840,  xxv,  99. 


EARLIER    OBSERVATIONS    ON    THE    TRANSMISSIBILITY    OF    CANCER      51 

several  small,  round,  bluish  nodules  were  found  in  the  lungs.  When 
submitted  to  the  microscope,  they  appeared  without  doubt  to  be 
carcinomata.  Virchow/  however,  who  saw  the  drawings  of  these 
tumors,  said  that  the  structure  was  more  similar  to  that  of  spontan- 
eous cancer  in  the  dog  than  to  that  of  carcinoma  as  it  occurred  in 
the  human  subject. 

Lebert's  treatise  on  cancer^  contained  the  description  of  an  experi- 
ment performed  in  conjunction  with  Follin.  Part  of  a  mammary 
cancer  was  emulsified  in  water  and  about  sixty  or  eighty  grams 
of  the  resulting  fluid,  in  which  the  presence  of  cancer  cells  had  been 
confirmed  by  the  microscope,  was  injected  into  the  jugular  vein  of  a 
dog.  The  animal  died  fifteen  days  afterward,  and  the  autopsy  dis- 
closed a  number  of  nodules  in  the  walls  of  the  heart,  beside  some  of 
smaller  size  in  the  liver,  all  of  which  contained  cancer  cells  with  round 
or  elliptical  nuclei  possessing  one  or  more  nucleoli,  while  numerous 
free  nuclei  were  also  present  in  the  preparations.  Lebert  did  not 
believe,  however',  that  this  single  experiment  was  of  any  great  signi- 
ficance and  declined  to  draw  definite  conclusions  therefrom,  realiz- 
ing that  the  dog  might  have  been  the  subject  of  spontaneous  cancer 
when  the  injection  was  first  undertaken. 

Many  investigators  beside  Dupuytren  had  reported  their  failure 
to  transplant  human  tumors  iruto  animals,  and  with  the  idea  that  the 
miscarriage  of  their  efforts  might  have  been  due  to  the  length  of  time 
intervening  between  removal  and  implantation,  Billroth  ^  planned  a 
series  of  experiments  in  which  this  period  should  be  reduced  to  a 
minimum.  He  inoculated  three  dogs  subcutaneously  and  six  intra- 
venously, but  with  negative  results  in  every  case  despite  his  care- 
ful technic.  For  the  subcutaneous  inoculations  two  carcinomata 
and  a  giant  cell  sarcoma  were  used,  while  for  the  intravenous  three 
carcinomata,  a  struma,  a  lymphoma,  and  a  giant  cell  sarcoma  were 
chosen. 

Alberts  ^  was  the  first  to  appreciate  that  the  lesions  so  often  de- 

1  Die  krankhaften  Geschwiilste,  Berlin,  1863,  i,  87  (footnote). 

^  Traite  pratique  des  Maladies  cancereuses  et  des  Affections  curables  confondues  avec  le 
Cancer,  Paris,  1851,  136. 

^Wien.  med.  Woch.,  1867,  xvii,  1137,  1153. 

'^  Das  Carcinom  in  historischer  11.  experimentell-pathologischcr  Bezichung,  Jena,  1887,  183. 


52     e.JlRlier  observations  ox  the  til\xsmissibility  oe  cancer 

scribed  as  transplanted  carcinomata  might  have  been  septic  emboli, 
and  to  conduct  experiments  in  such  a  way  as  to  exclude  sepsis.  Tumors 
that  had  been  aseptically  removed  by  operation  were  inoculated  into 
dogs,  but  in  no  case  did  a  successful  result  ensue. 

Klebs  ^  examined  fragments  of  human  carcinoma  removed  from  the 
peritoneal  cavities  of  white  rats  at  varying  intervals  after  introduc- 
tion, and  found  that  in  the  great  majority  of  cases  the  epitheHal  con- 
stituents of  the  graft  had  vanished  by  the  third  day. 

Duplay  and  Cazin  -  transplanted  various  t^'pes  of  tumors  from 
man  into  different  locaKties  in  animals  of  several  species,  but  the  out- 
come was  always  unsuccessful,  even  when  they  tried  to  produce  by 
trauma  a  soil  suitable  for  implantation.  Nor  did  they  meet  mth  any 
more  favorable  results  after  the  introduction  of  fragments  that  had 
been  kept  for  a  period  outside  the  body  to  allow  the  life  cycle  of  a 
h}^othetical  parasite  to  be  completed,  in  accordance  with  the  sugges- 
tion of  Metchnikoff.^  The  authors  decided  that  mahgnant  tumors 
did  not  appear  to  be  transmissible  from  one  species  of  animal  to  an- 
other. 

This  conclusion  may  be  accepted  as  representative  of  most  authori- 
ties, and  even  where  inoculations  have  been  made  into  species  so 
closely  related  to  man  as  the  anthropoid  apes,  the  attempted  transfer 
has  failed,  as  has  been  shown  by  the  work  of  Roux  and  Metchnikoff ,^ 
and  of  Jobling.^  The  reputedly  successful  results  have  all  been 
submitted  to  careful  scrutiny  and  found  wanting  in  one  respect  or 
another,  v.  Hansemann,^  for  example,  ha^^ing  pointed  out  that  typical 
metastases  have  never  been  described,  although  their  presence  would 
be  a  most  important  proof  that  implantation  had  been  accompUshed. 
Ribbert  ^    has  said    that    transplantation  could    be    performed  only 

^  Deut.  med.  Woch.,  1890,  xvi,  710. 
^  Semaine  med.,  1892,  xii,  61. 

Compt.  reiid.  de  I'Acad.  des  Sc,  1892,  cxiv,  325. 

Semaine  med.,  1893,  xiii,  329. 
'  Ann.  de  I'lnst.  Past.,  1892,  \d,  158. 
*  Bull,  de  I'Acad.  de  Med.,  1903, 1,  loi. 
^  See  Flexner,  Med.  Record,  1909,  Ixxv,  783. 

Monographs  on  Medical  and  Allied  Subjects,  Rockefeller  Institute,  New  York,  1910, 
No.  I,  120. 

^  Berl.  kUn.  Woch.,  1905,  xlii,  314. 

^  Verhandl.  d.  deutschen  path.  Gesellsch.,  1904,  S^e  Tagung,  104. 


EARLIER    OBSERVATIONS    ON    THE    TRANSMISSIBILITY    OF    CANCER       53 

between  individuals  of  the  same  or  of  a  very  closely  related  species, 
and  has  extended  this  rule  to  include  tumors,  since  no  satisfactory 
evidence  of  their  transfer  from  man  to  the  lower  animals  has  yet 
been  adduced. 

TUMOR   TRANSPLANTATION   WITHIN   THE    SAME   SPECIES 


(jHanaujJ  described  the  first  successful  transfer  of  carcinoma  within 
the  same  species.  Involving  the  vulva  of  an  old  rat  there  was  dis- 
covered an  ulcerated  cancer  which  had  metastasized  in  the  inguinal 
lymph  nodes  on  both  sides  and  in  those  of  the  axilla  on  the  right. 
Microscopical  examination  showed  that  it  was  a  keratinized  squamous 
cell  carcinoma.  A  fragment  from  one  of  the  still  unulcerated  nodes 
was  sewn  under  the  skin  of  the  scrotum  in  two  old  rats.  One  of  these 
animals  died  forty- seven  days  after  inoculation,  presenting  a  few  small 
nodules  on  the  quasi-mesentery  of  the  right  vas  deferens.  The  omen- 
tum-like  structure  which,  in  the  rat,  accompanies  the  vasa  spermatica 
interna,  was  studded  with  tumors,  while  the  great  omentum  had  been 
converted  into  a  nodular  mass.  The  small  omentum  was  also  in- 
volved, and  behind  the  stomach  and  between  this  organ  and  the 
spleen,  were  still  other  growths.  Microscopical  examination  of  two  of 
the  nodules  in  the  omentum  showed  that  they  were  carcinomata  of  ex- 
actly the  same  character  as  the  tumor  which  had  been  inoculated.  En- 
couraged by  these  findings,  Hanau  examined  the  second  rat  on  the  fifty- 
ninth  day  after  implantation  and  discovered  a  round  ulcer  affecting  the 
prepuce,  and  a  firm  movable  tumor  in  the  right  half  of  the  scrotum 
about  one-half  the  size  of  the  testicle.  On  the  sixty-first  day  this  rat 
was  sacrificed.  No  trace  of  epithelial  proliferation  was  found  in  the 
ulcer,  but  on  the  right  gubernaculum  hunteri  there  was  a  flat,  white 
nodule  about  2.5  millimeters  in  diameter,  while  between  the  testicle  and 
the  tail  of  the  epididymis  lay  the  larger  growth  which  had  been  felt 
during  life.  A  complete  histological  description  of  Hanau's  material 
has  been  published  by  Jenny.^ 

Pfeiffer,^  in  an  article  on  the  pathogenic  protozoa,  said  incident- 

1  Forlschritte  der  Med.,  1889,  vii,  321. 

Arch.  f.  klin.  Chir.,  (v.  Langenbeck),  1889,  xxxix,  678. 
"^  Arch.  f.  klin.  Chir.,  (v.  Langenbeck),  1895,  li,  269. 
*  Centralbl.  f.  Bakt.  etc.,  erste  Abt.,  Orig.,  1890,  viii,  802. 


54       EARLIER    OBSERVATIONS    ON    THE    TRANSMISSIBILITY    OF    CANCER 

ally  and  without  giving  any  details  regarding  the  experiment,  that 
he  had  succeeded  two  years  previously  in  transferring  a  melanotic 
carcinoma  of  the  mouse  to  other  mice. 

V.  Eiselsberg  ^  discovered  a  tumor  in  an  adult  rat  invoMng  the 
right  shoulder  and  about  the  size  of  a  hen's  egg,  hard,  nodular,  and 
movable  on  the  underlying  parts.  The  examination  of  fragments 
removed  for  diagnosis  proved  that  the  growth  was  a  spindle  cell  sar- 
coma. Some  days  later  portions  of  the  growth  were  excised  and 
sewn  into  mesenteric  folds  in  two  half-grown  rats.  The  tumor  rat 
having  died  under  the  anesthetic,  an  autopsy  was  immediately  under- 
taken, during  the  course  of  which  it  was  found  that  the  neoplasm  was 
connected  by  dense  adhesions  to  the  periosteum  of  the  scapula,  the 
bone  itself,  however,  ha\'ing  been  spared.  Nothing  was  said  of  the 
presence  of  metastases.  In  the  second  month  follomng  inoculation 
the  two  rats  were  examined  under  narcosis.  In  one  there  was  nothing 
abnormal,  but  in  the  abdomen  of  the  second  there  was  discovered  a 
tumor  the  size  of  a  nut.  Five  months  after  inoculation  this  rat  died 
during  the  night,  and  examination  twelve  hours  later  disclosed  a  firm 
nodular  tumor  in  the  mesentery,  about  the  size  of  a  hen's  egg.  .No 
other  pathological  condition  was  encountered.  The  microscopic 
structure  of  the  daughter  tumor  was  identical  with  that  of  the  spon- 
taneous growth  except  that  a  larger  number  of  spindle  cells  were 
present.  A  fragment  was  immediately  transplanted  into  another 
rat  but  ^\ithout  result  —  doubtless,  said  v.  Eiselsberg,  because  the 
tumor  cells  were  already  dead. 

A  tumor  about  as  large  as  a  hazel-nut  was  found  by  Morau  -  in  the 
axilla  of  a  white  female  mouse  of  unknown  age.  The  nodule  was  re- 
duced to  an  emulsion,  which  was  inoculated  subcutaneously  into  other 
mice,  and  among  these  a  number  of  tumors  were  found  three  months 
later.  From  one  of  the  growths  of  this,  the  first  generation,  cultivation 
was  continued  for  about  three  years,  seventeen  transfers  being  made 
in  all.  IMorau  drew  the  following  conclusions  from  his  series  of  experi- 
ments :  CyUndrical  epitheliomata  can  be  transferred  to  other  mice  by 

^  V/ien.  klin.  Woch.  1890,  iii,  927. 

2  Compt.  rend.  Soc.  Biol.,  1891,  xliii,  289. 

Compt.  rend,  de  I'Acad.  des  Sc,  1893,  cxvii,  62. 

Arch,  de  Med.  exp.  et  d'Anat.  path.,  1894,  vi,  ()Tj. 


EARLIER   OBSERVATIONS    ON    THE    TRANSMISSIBILITY    OF    CANCER      $5 

inoculation ;  heredity  plays  a  considerable  role  in  the  development 
and  evolution  of  these  tumors ;  traumatism  hastens  and  favors  their 
generalization ;  pregnancy  accelerates  their  growth  ;  the  tumors  possess 
a  variable  toxicity,  which  may  destroy  the  host's  life ;  they  seem  to 
lose  in  virulence  as  they  develop  in  new  animals ;  when  they  are  not 
ulcerated,  they  do  not  contain  microbes. 

Firket  ^  published  a  preliminary  note  describing  the  transfer  of  a 
spindle  cell  sarcoma  from  rat  to  rat.  A  fragment  from  one  of  the 
many  abdominal  tumors  in  the  animal  primarily  affected  was  trans- 
planted into  the  peritoneal  cavity  of  another  rat,  which  died  about 
six  weeks  later  with  generalized  growths  in  the  abdomen.  Grafts 
from  this  generation  were  transplanted  into  three  rats,  in  all  of  which 
growth  took  place,  and  with  one  of  the  resulting  tumors  two  other 
rats  were  ingrafted,  one  of  them  living  long  enough  to  develop  small 
nodules.  The  tumor  retained  its  original  sarcomatous  structure 
throughout  the  experiment. 

VeHch  -  discovered  in  the  femur  of  a  white  rat  a  subperiosteal 
sarcoma,  a  portion  of  which,  transplanted  subcutaneously  into  an- 
other rat,  produced  a  nodule  as  large  as  a  walnut  after  a  week's  growth. 
This  increased  so  rapidly  in  size  that  in  three  weeks  it  had  attained  a 
length  and  breadth  of  five  centimeters,  and  a  thickness  of  three.  At 
the  end  of  six  weeks,  when  the  rat  died,  the  tumor  was  about  one- 
third  the  length  of  its  body.  Before  the  death  of  the  animal  pieces 
had  been  removed  from  the  tumor  and  implanted  in  three  rats,  in  all 
of  which  nodules  were  appreciable  a  few  days  after  inoculation.  Al- 
together this  sarcoma  was  carried  through  eight  generations,  but  the 
growth  energy  became  progressively  more  feeble  until  finally  the  tumor 
died  out.  VeHch  recorded  the  fact  that  the  rats  used  after  the  eighth 
generation  were  from  another  source  and  considered  the  possibiHty 
that  a  strange  breed  might  not  have  offered  favorable  conditions  for 
growth,  dismissing  it,  however,  because  a  decrease  in  proliferative 
energy  had  set  in  before  the  new  strain  was  introduced  into  the  ex- 
periment. The  daughter  tumors  were  all  spindle  cell  sarcomata  and 
similar  in  every  respect  to  the  primary  growth. 

To  none  of  these  communications  was  any  especial  attention  devoted, 

^Bull.  de  I' Acad.  Royale  de  Med.  de  Belgique,  1892,  vi,  1147. 
2  Wien.  med.  Blatter,  1898,  xxi,  711,  729. 


56      EARLIER    OBSERVATIONS    ON    THE    TRANSMISSIBILITY    OF    CANCER 

for  their  significance  was  not  grasped  at  the  time  of  their  appearance ; 
and  it  was  only  after  the  earlier  articles  of  Jensen,  Loeb,  and  Borrel 
had  been  pubhshed  that  experimental  pathologists,  appreciating  the 
possibiHties  which  they  had  until  then  neglected,  commenced  a  con- 
certed attack  upon  the  biological  side  of  the  cancer  problem.  A 
communication  from  the  pen  of  Jensen^  which  initiated  this  era  of 
acti\ity,  has  became  a  cj^s_sic  in  the  literature  of  cancer  research  as  the 
masterly  paper  of  Koch  had  become  classic  in  the  annals  of  tuber- 
culosis —  for  its  evidences  of  patient,  accurate,  and  exhaustive  in- 
vestigation. Jensen  -  had  described  previously  the  results  attend- 
ing the  transplantation  of  tumors  from  mouse  to  mouse,  but  the  fruits 
of  his  labor  first  became  accessible  to  the  general  pathological  public 
upon  the  appearance  of  an  article  in  the  German  literature.  The 
facts  recorded  in  the  earher  papers  were,  in  short,  that  he  had  been  able 
to  transmit  a  mouse  cancer  through  eight  generations,  that  nqjmicro- 
organisms  had  been  found  in  it,  and  that  experiments  deahng  with  the 
resistance  of  the  cancer  cell  to  various  agents  had  been  undertaken. 

In  the  German  paper  Jensen  described  in  great  detail  the  tumor  and 
the  results  attendant  upon  its  transplantation.  The  primar}^  growth 
was  about  the  size  of  a  hazel-nut,  situated  under  the  skin  of  the  back, 
and  microscopical  examination  disclosed  the  fact  that  it  was  a  t}'pical 
carcinoma.  Daughter  tumors  were  of  entirely  similar  architecture,  a 
relatively  sparse  stroma  inclosing  a  large  number  of  alveoli  contain- 
ing cells  of  various  contours.  The  cell  bodies  were  large  and  fairly 
homogeneous,  the  nuclei  large  and  provided  mth  nucleoli  and  a  promi- 
nent chromatin  network.  As  a  rule  the  mitotic  figures,  which  were  by 
no  means  rare,  were  of  the  normal  type,  although  atypical  forms 
were  occasionally  to  be  found.  A  part  of  the  nodule  was  emulsified  in 
physiological  saHne  solution  and  a  small  amount  of  this  suspension  was 
inoculated  subcutaneously  into  five  mice,  three  of  which  developed 
tumors  that  were  afterward  transplanted  into  other  series  of  mice. 
The  experiments  had  extended  over  a  period  of  two  and  a  half  years, 
the  tumor  had  been  carried  through  nineteen  generations,  and  would 
grow  in  about  half  of  the  mice  inoculated.     During  all  the  time  that 

^  Centralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1903,  xxxiv,  28,  122. 
^Hospitalstideirde,  1902,  x,  489. 
HospUalsiidende,  1903,  xi,  549,  5S1. 


EARLIER   OBSERVATIONS    ON   THE    TRANSMISSIBILITY    OF    CANCER      57 

the  neoplasm  had  been  under  cultivation  metastases  in  internal  organs 
had  never  been  discovered,  and  the  regional  lymph  nodes,  while  usu- 
ally swollen,  were  only  once  found  to  contain  anything  like  a  secondary 
deposit.  Unfortunately,  however,  the  specimen  had  been  mislaid  be- 
fore it  was  ready  for  examination. 

The  details  of  Jensen's  experiments,  in  common  with  those  of  the 
investigations  which  have  been  prosecuted  by  the  two  succeeding 
authors,  will  be  discussed  in  the  following  chapters  under  their  ap- 
propriate headings. 

The  period  that  saw  the  pubHcation  of  Jensen 's  first  article  witnessed 
also  the  accounts  of  Loeb's  early  work.^  Loeb  discovered  a  cystic 
sarcoma  of  the  thyroid  in  a  white  rat  and  succeeded  in  transmitting 
it  to  other  rats  by  inoculation,  but  not  by  causing  its  ingestion.  Dur- 
ing the  fifteen  months  that  the  growth  had  been  under  propagation 
the  histological  structure  had  been  preserved  unaltered.  Neither 
the  primary  tumor  nor  those  belonging  to  subsequent  generations  had 
produced  metastases,  although  in  one  instance  tumor  cells  had  been 
found  penetrating  a  blood  vessel. 

In  a  succeeding  paper  Loeb  -  reported  that  the  neoplasm  in  ques- 
tion had  been  carried  through  about  forty  generations  in  the  course 
of  twenty  months,  but  had  finally  become  so  infected  that  further 
propagation  had  been  rendered  impossible.  Other  rat  tumors  had, 
however,   been   successfully   transplanted. 

While  the  experiments  of  Jensen  and  Loeb  were  in  progress,  Bor- 
rel  ^  was  engaged  upon  the  same  problem.  Although  transplantation 
succeeded  in  only  about  lo  %  of  the  mice  inoculated,  daughter  tumors 
were  obtained  of  such  rapid  growth  that  after  the  expiration  of  forty 
days  they  weighed  more  than  the  mice  themselves.  Metastases  were 
discovered  at  autopsy  in  the  blood  vessels  of  the  lungs  as  well  as  in 
the  lymph  nodes,  always  preserving  the  structure  of  the  main  growth. 

A  critical  review  of  the  work  of  Jensen's  antecedents  will  be  found 
in  a  summary  by  Sailer^  of  the  literature  relating  to  the  inocula- 
bihty  of  carcinoma. 

'^  Jour.  Med.  Research,  1901,  N.S.,  i,  28. 
Arch.  f.  path.  Anal.,  etc.,  (Virchow),  1902,  clxvii,  175. 

^  Jour.  Med.  Research.,  1902,  N.S.,  iii,  44.  ^  Ann.  de  VLnst.  Past.,  1903,  xvii,  112. 

^American  Jour,  of  the  Med.  Sciences,  1900,  cxx,  190. 


CHAPTER  IV 
THE  TRANSPLANTED   TUMOR 

THE    STROMA   REACTION 

As  soon  as  it  had  been  demonstrated  that  mahgnant  growths  were 
transmissible,  it  was  necessary  to  know  whether  the  cells  of  the 
daughter  tumors  were  direct  descendants  of  those  that  had  been 
introduced  in  the  graft,  or  whether  they  arose  from  the  tissues  of  the 
new  host.  This  was,  of  course,  tantamount  to  asking :  Is  the  transfer 
of  a  tumor  an  instance  of  transplantation  or  of  infection  ? 

The  vital  importance  of  settling  this  question  did  not  escape  Jensen.^ 
He  followed  carefully  the  fate  of  implanted  fragments,  examining 
them  at  daily  intervals  after  transplantation,  and  found  that,  while 
many  of  the  parenchymal  cells  perished  soon  after  their  introduction 
into  the  new  animal,  there  was  still  a  fairly  large  number  that  remained 
alive,  and  that  in  larger  grafts  the  cells  able  to  retain  their  vitality 
were  those  situated  at  the  periphery.  The  stroma  of  the  newly  in- 
grafted tumor  became  hyaline  and  nearly  all  the  connective  tissue  cells 
in  the  ceritral  parts  disappeared,  while  at  the  same  time  many  recently 
formed  blood  vessels  and  fibroblasts  appeared  about  the  fragment  and 
in  its  margin.  The  final  fate  of  the  stroma  was  not  absolutely  clear 
to  Jensen,  but  it  seemed  as  though  it  were  gradually  penetrated  from 
without  by  blood  vessels  and  fibroblasts  and  that  it  eventually  suffered 
absorption,  although  there  remained  the  possibility  that  part  of  it 
might  continue  to  live.  The  surviving  cells  of  the  parenchyma  were 
always  sharply  demarcated  from  those  surrounding  them,  and  there 
was  no  evideiice  of  the  creation  ^f  tumor  cells  from  any  of  the  eLlements 
of  the  host.  Without  doubt,  therefore,  the  process  was  a  real  trans- 
planteiion. 

^  Centralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1903,  xxxiv,  127. 
58 


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THE    TRANSPLANTED    TUMOR  59 

Loeb^  was  unable  to  decide  definitely  between  transplantation  and 
infection,  possibly  because  his  initial  observations  were  conducted 
with  a  sarcoma  —  a  tumor  type  in  which  the  analysis  of  early  growth  is 
fraught  with  the  greatest  difficulty.  In  a  later  article  he^  expressed  the 
view  that  the  peripheral  cells  of  the  graft  remained  aHve  and  developed, 
mingling  with  the  surrounding  elements  of  the  connective  tissue.  It 
was  very  probable  that  tumor  cells  themselves  were  transplanted  in 
addition  to  the  tumor-producing  agency. 

V.  Leyden,^  while  admitting  that  inoculated  tumors  resulted  from 
the  proHferating  ceUs  of  the  transplanted  graft,  could  understand  this 
fact  only  by  assuming  the  presence,  of  an  intracellular  parasite.  This 
supposition,  he  thought,  did  not  oppose  the  conceptions  which  had  been 
developed  by  the  pathologist,  and  was,  moreover,  the  only  one  capable 
of  explaining  the  phenomena  associated  with  cancer  in  man. 

Jensen's  findings  were  confirmed  and  amplified  by  Bashford  and 
Murray^  in  conjunction  with  Cramer,^  through  the  investigation  of 
several  tumors  with  parenchyma  and  stroma  of  different  types.  The 
results,  which  were  similar  in  all  the  growths  studied,  were  described 
most  fully  for  Jensen's  tumor,  which  had  been  submitted  to  a  more  ex- 
tensive examination  than  the  others.  The  authors  found  that  the  first 
evidence  of  reaction  to  the  graft  was  a  rapid  aggregation  of  polymor- 
phonuclear leucocytes  in  the  surrounding  tissues  of  the  host,  beginning 
about  two  hours  after  the  introduction  of  the  tumor  fragment  and  of 
short  duration  only.  The  leucocytes  collected  about  any  necrotic 
material  present  and  even  penetrated  between  the  tumor  cells.  About 
fifteen  hours  after  the  introduction  of  the  graft  there  occurred  prolifera- 
tive changes  in  the  surrounding  areolar  connective  tissue  of  the  host, 
the  cells  of  which  became  shorter  and  thicker,  while  their  nuclei  divided 
by  amitosis.  The  proliferating  cells  migrated  into  the  cleft  which  origi- 
nally separated  the  connective  tissue  of  the  host  from  the  newly  intro- 
duced fragment,  and  appHed  themselves  to  the  surface  of  the  graft. 
The  stroma  had  already- become  hyahne  after  twenty- four  hours,  and 
commencing  degeneration  could  often  be  detected  in  its  cells.  Such 
changes  were  even  more  distinct  after  thirty-six  hours,  and  by  this  time 

^  Jour.  Med.  Research,  1901,  N.S.,  i,  37.  "^  Jour.  Med.  Research,  1902,  N.S.,  iii,  52. 

^  Berl.  klin.  Woch.,  1905,  xlii,  348.  *  Proc.  Roy.  Soc,  1904,  Ixxiii,  70. 

^  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  24. 


6o  THE    TRAXSPLAXTED    TUMOR 

the  nuclei  had  become  small,  irregular,  and  deeply  staining,  while  fatty 
degeneration  of  the  cytoplasm  had  set  in.  The  capiUaries  of  the  graft 
w-ith  their  blood  corpuscles  were  still  recognizable,  although  the  endo- 
thehum  showed  degenerative  changes.  Outside  of  the  graft  fibrin  fila- 
ments had  appeared  in  the  exudate  and  amitotic  di\dsion  of  the  con- 
nective tissue  cells  was  still  in  progress,  while  spindle-shaped  wandering 
cells  had  begun  to  penetrate  the  transplanted  tumor.  Three  days  after 
inoculation  the  cleft  between  the  tumor  and  the  host's  tissues  was 
almost  obhterated,  and  wandering  cells  could  be  distinguished  in  the 
interstices  of  the  graft,  where  they  were  di\"iding  by  mitosis.  ^Mitotic 
di^'ision  was  in  e\idence,  also,  in  the  fibroblasts  of  the  host  nearest  the 
tumor.  In  the  transplanted  stroma  the  collagenous  fibrils  had  fused 
into  homogeneous  glassy  bundles  and  the  connective  tissue  cells  ex- 
hibited, beside  chromatolysis.  unmistakable  fatty  degeneration  of  their 
protoplasm.  Xo  development  of  new  blood  vessels  had  yet  occurred, 
and  the  whole  mass  of  transplanted  tissue  remained  ^\'ithout  vascular 
supply.  Four  days  after  transplantation,  however,  an  ingrowth  of 
capiUaries  had  taken  place  and  vascularization  was  in  su£h  rapid 
progress  that  aU  stages  of  new  capillary  formation  might  be  found 
in  the  same  specimen.  Fibroblasts  frorn^  the_host  were  streaming 
into  the  tumor  from  every  side,  some  of  them  appearing  to  exercise 
a  phagocytic  function  and  finally  to  degenerate,  while  others  sur^dved 
to  form  the  new  stroma.  The  old  connective  tissue  stiU  remained,  but 
was  in  the  last  stages  of  degeneration.  From  four  days  onward  there 
was  a  continual  recession  of  the  stroma  originally  introduced,  and  an 
orderly  progress  of  vascularization  until,  by  the  eleventh  day.  fibrils  of 
new-formed  coUagen  could  be  found  in  the  new  stroma  which,  at  the 
eighth,  had  been  very  cellular. 

Thus  the  cancer  cells  manifested  the  faculty  of  continuous  growth 
and  a  power  to  make  the  tissues  of  the  new  host  subserA-ient  to  their 
needs.  The  proHferative  power,  however,  attached  only  to  the 
parenchymal  cells,  and  was  not  acquired  by  any  of  the  elements 
with  which  they  had  come  in  contact  in  successive  hosts. 

This  stroma  reaction  was  shown  further  to  be  a  specific  one.  That  is 
to  say,  the  character  taken  on  by  the  newly  formed  scaft'olding  was 
determined  not  by  the  reacting  tissues  themselves,  but  by  some^uiij 
kiiown  influence  exerted  upon  them  by  the  parenchymal  cells,  which 


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THE   TRANSPLANTED    TUMOR  6 1 

were  able  to  force  the  tissues  of  each  new  host  to  furnish  a  stroma 
typical  for  the  tumor  to  which  they  belonged. 

EhrHch/  in  accepting  the  stroma  reaction,  assigned  to  the  tumor 
cell  two  specific  powers,  one  of  which  acted  upon  fibroblasts,  the  other 
upon  angioblasts.  The  former  property  was  exercised  by  the  trans- 
plantable carcinomata  and  sarcomata  while  the  latter  was  very  distinct 
in  a  transplantable  chondroma,  the  cells  of  which  could,  however,  be 
robbed  of  their  chemotactic  action  upon  the  angioblasts  by  exposure 
to  heat  or  cold  or  by  transplantation  into  an  animal  highly  resistant 
to  the  growth.  In  such  cases  the  tumors  proliferated  without  the 
participation  of  the  vascular  system,  "But  grew  ^slowly,  were  white 
in  color,  and  not  infrequently  necrotic. 

Gierke  ^  also  was  of  the  opinion  that  differences  could  be  discerned 
in  this  reaction  in  accordance  with  the  varying  extent  to  which  the 
connective  tissues  and  blood  vessels  responded  to  stimulation,  and 
described  a  fibroplastic  and  an  angio plastic  type.  If  the  two  in- 
fluences were  in  equilibrium  well-nourished  carcinomata  would  result, 
but  should  the  fibroplastic  type  predominate  nutrition  of  the  cell  nests 
would  suffer,  and  in  this  way  might  be  explained  the  necrosis  of  part 
or  all  of  a  neoplasm.  If  the  angioplastic  sway  preponderated  there 
would  be  formed  a  rich  supply  of  vessels  and  but  little  connective 
tissue,  a  condition  which  had  been  described  by  Apolant  in  the  case 
of  the  hemorrhagic  tumors. 

INCREASE    OF    VIRULENCE    OR    ADAPTATION? 

Although  all  observers  have  agreed  that  once  a  tumor  has  been  trans- 
planted it  is  the  rule  for  it  to  yield  a  gradually  increasing  number  of 
successes  upon  protracted  cultivation,  it  has  not  been  decided  whether 
this  is  to  be  looked  upon  as  an  increase  in  virulence  on  the  part  of  the 
cancer  cell,  or  as  an  augmentation  of  its  power  to  adapt  itself  to  a  new 
host.  The  former  hypothesis  was  advanced  by  Ehrhch  and  has  been 
consistently  upheld  by  him,  while  the  latter  has  found  defenders  in 
Bashford  and  the  adherents  of  his  school. 

^  Zeitschrift  f .  Krebsforsch.,  1907,  v,  70. 
^  Beitr.  zur.  path.  Anat.,  etc.,  (Ziegler),  1908,  xliii,  340. 
Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  129. 


62  THE    TRANSPLANTED    TUMOR 

Ehrlich^  held  it  possible  to  achieve  increased  or  even  maximal  vir- 
ulence by  transplanting  at  short  intervals  the  rapidly  growing  tumors 
in  each  series.  In  this  way  he  had  obtained  tumors  with  an  energy  of 
growth  that  had  never  been  equalled  either  in  the  laboratory  or  in 
clinical  experience,  although  such  a  result  could  not  be  attained  with 
every  strain.  An  analogy  for  the  increase  of  tumor  virulence  could  be 
found  in  bacteriology  where  it  was  necessary,  in  order  that  the  viru- 
lence of  a  culture  might  be  maintained,  to  subject  it  to  continual  passage 
through  animals  or  to  transfer  it  frequently  to  a  favorable  medium. 

Apolant^  distinguished  sharply  between  two  factors  comprised  in 
the  conception  of  virulence  —  trans plantahility,  measured  by  the 
number  of  daughter  tumors,  and  proliferative  energy,  evaluated  by 
the  rate  of  growth.  While  in  general  slowly  growing  tumors  gave  a 
meager,  and  rapidly  growing  a  generous  outcome  after  transplanta- 
tion, there  were  exceptions  to  the  rule,  among  which  EhrHch's  prop- 
agable  chondroma  was  a  striking  example,  for  although  this  growth 
had  yielded  from  the  first  a  maximal  number  of  daughter  tumors,  the 
proHferative  energy  of  its  cells  had  remained  extremely  feeble  in  spite 
of  several  years  of  cultivation.  Notwithstanding  the  fact  that  it  had 
been  possible  with  many  tumors  to  augment  both  the  transplantabihty 
and  the  energy  of  proHferation,  such  a  transmutation  could  not  always 
be  brought  about,  certain  strains  showing  individual  pecuHarities  as 
regarded  the  increase  of  their  virulence.  These  differences  were  ex- 
hibited both  in  the  degree  to  which  transplantabihty  could  be  stimu- 
lated and  in  the  rapidity  at  which  the  optimum  inoculation  result  was 
reached,  but  the  rate  of  growth  apparently  could  be  hastened  only  to 
a  certain  point  specific  for  each  individual  strain.  It  was  at  its  lowest 
in  the  chondroma,  variable  among  the  carcinomata,  and  enormous 
among  the  sarcomata,  the  tumors  last  named  often  reaching  within 
three  or  four  weeks  a  size  equal  to  that  of  the  mouse  in  which  they 
were  growing.  Such  energy  of  growth  was  without  analogy  in  human 
oncology. 

Apolant  did  not  think  that  Bashford's  hypothesis  of  adaptation 
sufficed  to  explain  either  the  fact  that  tumors  could  be  made  to  grow 

1  Arh.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  80. 
Zeitschrift  f.  Krehsforsch.,  1907,  v,  62. 

2  Zeitschrift  f.  dig.  Physiol.,  1909,  ix,  Sammelreferat,  69. 


THE    TEANSPLANTED    TUMOR  63 

after  a  time  in  strange  races  of  mice,  or  that  it  was  possible  to  achieve 
an  increase  in  virulence.  Conceptions  of  the  real  nature  of  these 
phenomena  had  been  hitherto  very  vague,  and  words  rather  than 
ideas  had  been  employed  in  explaining  them.  It  was  accordingly 
very  gratifying  to  find  that  the  question  had  been  simpHfied  through 
the  following  investigations  carried  out  upon  trypanosomes  by  Ehrlich, 
in  common  with  Rohl  and  Fraulein  Gulbranson. 

If  an  infected  mouse  were  treated  with  one  of  the  newer  and  very 
active  arsenic  preparations,  but  without  being  given  an  amount  quite 
large  enough  to  cure  it  entirely,  the  trypanosomes  would  disappear 
from  the  blood  for  a  considerable^Jtime  and,  through  the  absorption 
of  the  parasites  killed  by  the  medicament,  there  would  occur  the 
elaboration  of  an  abundant^  qioantity  of  antibodies.  But,  as  all  the 
parasites  had  not  been  destroyed,  recurrence  would  take  place  sooner 
or  later,  the  advent  of  which  could  be  explained  by  one  of  two  possibili- 
ties —  either  that  the  antibodies  had  disappeared,  or  that  the  try- 
panosomes had  become  proof  against  them.  Actually  the  latter  was 
what  happened,  for  if  one  introduced  trypanosomes  cultivated  during  a 
recurrent  attack  into  mice  which,  having  been  cured  of  an  infection, 
enjoyed  the  possession  of  antibodies,  these  injected  organisms  would 
be  able  to  flourish  as  vigorously  as  in  normal  animals,  although  in- 
oculation of  the  immune  mice  with  their  original  strain  would  be  at 
first  unsuccessful,  because  this  strain  would  have  become  susceptible 
to  the  action  of  the  antibodies  which  had  conferred  immunity  on  these 
mice.  There  was  here  in  play  a  fundamental,  hereditary,  biological 
alteration,  the  nature  of  which  Ehrhch  had  explained  as  follows.  The 
original  parasites  had  a  certain  type  of  nutriceptor  (a  receptor  for 
assimilating  nutriment).  A,  which,  after  having  been  killed,  acted  as 
antigen  in  producing  an  antibody  which  could  only  be  fastened  by 
this  group.  If  all  the  A;££££piQrs,of  a  parasite  were  occupied  by  anti- 
bodies^  and  thus  eliminated  from  the  absorption  of  nourishment,  the 
cell  died,  unless  through  the  stimulation  of  hunger  a  new  group,  B, 
already  potentially  present  and  unrelated  to  the  antibody  A,  could  be 
produced.  The  trypanosome  that  formerly  obtained  food  through  its 
A-nutriceptors  now  nourished  itself  by  means  of  its  B-receptors,  so  that 
there  had  occurred  the  disappearance  of  one  class  of  receptor  in  favor 
of  a  new  one. 


64  THE    TRANSPLANTED    TUMOR 

But  in  the  same  cell  there  might  be  still  other  potential  rudiments 
and  Ehrlich  had,  in  fact,  succeeded  in  provoking  in  one  species  of 
trypanosome  ten  different  kinds  of  receptor.  Generally,  however, 
only  one  group  was  produced  —  A  or  B  or  C,  etc.  This  was  the  unio 
type ;  when  two  or  more  groups  were  ehcited,  A  and  B  and  C, 
etc.,  the  varieties  were  called  binio,  ternio,  etc.  If  now  a  binio  con- 
taining, for  example,  groups  A  and  B,  were  to  attract  a  single  anti- 
body, that  is,  only  antibody  A  or  antibody  B,  death  would  not  occur 
and  the  binio  would  Hve  on  with  the  other  receptors.  It  followed, 
therefore,  that  the_antibody  in  such  a  case  would  have  no  deleterious 
effect  except  in  so  far  as  it  blockaded  one  source  of  nourishment; 
and,  as  from  one  trypanosome  ten  different  stable  unios  might  be 
evolved,  it  must  be  true  that  this  parasite  was  able  to  obtain  its 
nutrition  in  ten  different  ways  in  the  mouse  alone.  The  observation 
demonstrated  that  one  single  occurrence  could  produce  a  persistent 
change  in  the  cell  protoplasm.  An  alteration  like  this  would  be  suffi- 
cient to  confer  on  the  ceU  and  its  descendants  a  permanent  increase 
in  growth  energy,  for  to  a  case  of  this  sort  Weigert's  law  of  the  hyper- 
compensation  of  damaged  functions  was  quite  appHcable.  The 
disappearance  of  one  type  of  receptor.  A,  represented  a  cell  injury 
which  was  overcompensated  by  the  abundant  production  of  other 
receptors.  A  substance  able  to  bring  about  imm.ediately  such  a 
transformation  Ehrlich  had  called  a  growth  substance  ("  Wuchsstoff  ") , 
contrasting  it  with  the  food-stiiffs  ("  Nahrstoff e ") ,  which,  after 
assimilation,  maintained  the  constant  growth  of  the  cells,  and  of  which 
ten  varieties  had  been  demonstrated  for  the  trypanosomes. 

These  conceptions  could  be  transferred  to  the  study  of  maHgnant 
growths  without  further  formality.  In  a  tumor  cell  there  must  be 
present  a  number  of  potential  rudiments  beside  the  actual  nutriceptors 
suited  to  the  food  offered  by  the  affected  animal.  If  the  tumor  were 
transplanted  to  another  host,  three  occurrences  were  possible :  either  the 
new  soil  would  afford  the  same  nourishment  as  the  old  and  the  tumor 
could  accordingly  grow ;  or  the  host  would  proffer  food  that  none  of 
the  nutriceptors  was  able  to  grasp,  in  which  case  transplantation  would 
be  unsuccessful ;  or,  finally,  there  might  be  tendered  food  not  exactly 
like  the  old,  but  for  which  there  were  present  at  least  the  potential  rudi- 
ments of  nutriceptors.     In  this  case  those  cells  would  die  in  which  the 


THE    TRANSPLANTED    TUMOR  65 

development  of  potential  nutriceptors  had  not  occurred  with  sufficient 
promptitude ;  but  the  cells  which  had  been  stimulated  by  hunger  to 
produce  fresh  nutriceptors  would  be  able  to  survive  in  the  new  host, 
and,  furthermore,  their  proliferation  through  succeeding  generations 
would  be  assured,  the  newly  acquired  properties  being  hereditary  as 
they  were  in  the  trypanosomes. 

Apolant  considered  this  to  be  an  exact  scientific  explanation  for  the 
sudden  transformations  so  frequently  seen  after  the  introduction  of 
tumors  into  strange  races,  transformations  which,  as  with  the  trypano- 
somes, might  include  a  loss  of  sensitiveness  toward  the  original  race. 
The  conception  explained  also  increase  of  virulence  for,  through  an 
excess  of  nutriceptors  produced  in  answer  to  the  stimulus  of  hunger, 
there  were  assured  both  an  easier  estabhshment  and  a  more  vigorous 
proliferation  in  the  new  host. 

The  English  school,  headed  by  Bashford,  preferred  the  term  adap- 
tation to  increase  of  virulence.  Bashford^  thought  that  objective 
statements  should  be  substituted  for  loose  descriptions  Hke  "virulent" 
or  ''avirulent,"  and  that  the  initial  dose  should  be  stated,  since  it  so 
largely  determined  the  size  of  the  resulting  tumor.  When  this  dose 
was  unknown  no  judgment  of  the  growth  rate  was  possible. 

Murray^  called  attention  to  the  reservations  which  should  be  made 
in  comparing  the  growth  of  transplantable  carcinomata  to  the  cultiva- 
tion of  a  pathogenic  micro-organism  through  a  succession  of  susceptible 
animals.  The  augmentation  in  the  percentage  of  successful  inocula- 
tions and  in  the  speed  of  growth  could  be  referred  with  a  high  degree  of 
probability  to  the  rapidity  with  which  the  parenchymal  cells  adapted 
themselves  at  this  stage.  In  consequence  of  such  adaptation,  a 
progressively  larger  number  of  cells  survived  the  injuries  inseparable 
from  the  act  of  transplantation,  and  the  size  attained  by  the  tumors  in 
equal  periods  of  time  was,  therefore,  greater.  Once  this  preUminary 
stage  had  been  passed  the  rate  of  growth  and  percentage  of  success 
fluctuated  between  somewhat  wide  limits. 

Bashford,  Murray,  Haaland,  and  Bowen  ^  had  found  that  the  initial 
transfer  of  a  mahgnant  new  growth  from  the  spontaneously  affected 

^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  Introduction,  xxiii. 
^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  161. 
*  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  269. 


66 


THE    TRANSPLANTED    TUMOR 


animal  to  the  first  series  of  normal  ones  was  in  most  cases  attended 
with  great  technical  difficulties,  and  they  beheved  that  this  was  the 
result  of  a  failure  by  the  tumor  cells  to  adapt  themselves  to  altered 
conditions  of  existence  upon  their  removal  from  the  animal  in  which 
they  had  first  acquired  mahgnant  properties,  and  their  introduction 
into  normal  ones.  With  successi ve__^an^lantation ,  however,  there 
came  an  increase  in  the  number  of  cells  surviving  and  proliferating 


40  I   41  P   42  L  43  L   44  D  45  C   46  G   47  H 


49  C  50  L   51  L 


15%     20%     23%      30%       53%     53%       66%      78%     84%      37%      27%      27% 

Fig.  I. —  Diagram  to  illustrate  the  way  in  which  the  elimination  of  degenerating 
cells  by  repeated  transplantation  may  result  in  a  progressive  increase  in  the  per- 
centage of  success  in  a  strain  of  transplantations.  Each  large  square  represents 
the  constitution  of  the  parent  tiunor  of  the  batch  of  inoculations  whose  label  is 
printed  above  it,  as  measured  by  the  percentage  of  success  printed  below.  One 
hundred  inoculations  are  supposed  to  be  made  in  every  case,  and  the  number  of  small 
squares  left  clear,  corresponding  to  the  percentage,  shows  the  number  of  fragments 
which    developed   into  tumors. 


in  each  graft.  Whether  this  were  due  to  the  elimination  of  cells 
less  able  to  conform  to  varying  conditions,  or,  on  the  other  hand,  to  the 
acquisition  of  greater  adaptabihty,  growth  power,  and  resistance  to 
injury,  by  cells  at  first  barely  able  to  survive,  was  not  of  any  great 
moment.  It  seemed  probable  that  both  factors  were  reahzed  in 
propagation,  and  if  the  authors  incHned  to  ascribe  more  importance 
to  the  former  it  was  only  because  on  that  assumption  a  greater  number 
and  range  of  facts  could  more  easily  be  harmonized  and  brought  under 
review. 

Bashford,  Murray,  and  Cramer,^  during  the  propagation  of  Jensen's 
tumor  and  other  growths,  had  frequently  obtained  series  of  inoculations 
with  a  maximal  percentage  of  success.  The  method  of  repeated  sub- 
division of  the  parenchyma  into  the  small  grafts  necessary  for  the 
analysis  of  the  phenomena  of  proliferation  showed  that  each  maximum 

^Proc.  Roy.  Soc,  Series  B,  1907,  bcxix,  164. 
Third  Sci.  Report,  Imperial  Cancer  Research  Fimd,  London,  190S,  325,  336. 


THE    TRANSPLANTED    TUMOR  67 

was  followed  by  a  rapid  and  great  diminution  in  the  percentage  of 
success  and  that  this,  in  turn,  was  succeeded  by  an  increase  to  a  fresh 
maximum.  By  choosing  a  suitable  interval  for  the  inoculation  of 
tumors  which  had  been  selected  from  series  with  from  90  to  100  % 
of  success,  and  especially  by  increasing  the  initial_^ose,  the  authors 
had  been  able  to  evadg.  for  a  considerable  number  of  transferences  the 
diminution  usually  following  each  maximum.  This  outcome,  how- 
ever, was  artificial,  and  indicated  neither  an  increased  "virulence" 
of  the  tumor  cells  nor  a  uniform  energy  of  growth. 

They  ascribed  great  importance  to  the  nature  of  the  inoculated 
material.  Where  small  doses  gave  a  maximum  success,  large  doses 
might  do  so  as  well  and  produce  very  much  bigger  tumors  in  the 
same  time ;  but  on  the  other  hand,  in  those  cases  where  growth  could 
be  inhibited  by  the  simultaneous  absorption  of  tumor,  the  larger  doses 
would  be  much  less  successful.  The  absorption  of  tumor  tissue  was 
inversely  proportional  to  the  number  of  cells  growing  in  the  graft,  and 
whereas  full  doses  of  cells  in  the  positive  phase  of  growth  led  to  large 
tumors  and  no  immunity,  a  similar  amount  in  the  negative  phase 
yielded  very  few  tumors,  permitted  of  much  absorption,  and  produced 
a  high  proportion  of  resistant  animals.  Thus  the  "virulence"  of  the 
cells  of  a  single  tumor  fluctuated  between  negative  and  positive  phases 
of  growth  energy. 

Spontaneous  tumors  varied  considerably  in  the  ease  with  which 
they  could  be  propagated,  and  these  differences  had  been  regarded 
as  degrees  of  virulence.  Nevertheless  there  was  a  certain  amount  of 
evidence  to  show  that  such  tumors  fluctuated  in  growth  energy  in  a 
manner  similar  to  transplantable  growths.  Any  direct  conclusion 
regarding  the  "virulence"  of  a  spontaneous  tumor  drawn,  therefore, 
from  one  primary  transplantation,  might  be  upset  when  the  same 
growth  gave  an  opposite  result,  i.e.  when,  after  having  recurred,  it 
had  been  transplanted  a  second  time. 

The  term  "virulence",  was  for  this  reason  unfortunate,  and  had  to 
be  used  with  so  much  reservation  that  it  would  be  better  discarded 
altogether. 


68  THE    TRANSPLANTED    TUMOR 


STIMULATION   OF   GROWTH  POWER 


A  few  observers  have  reported  an  increase  of  proliferative  energy 
on  the  part  of  tumor  cells  exposed  to  various  physical  or  chemical 
influences. 

,  Thus  Clowes  and  Baeslack  ^  found  that  neoplasms  of  relatively  low 
growth  power  might  be  so  stimulated  by  incubation  at  a  temperature 
of  39°  to  41^.  or  by  exposure  to  mercuric  chloride,  potassium  cyanide, 
ammonium  fluoride,  and  mercuric  iodide,  in  solutions  of  suitable  con- 
centration, as  to  afford  a  larger  yield  of  more  rapidly  proliferating 
growths.  The  curious  paradox  was  noted  that  in  the  case  of  highly 
virulent  tumors  incubation  decreased  the  growth  energy. 

EhrHch,"  in  an  endeavor  to  reproduce  the  phenomenon  described 
by  Clowes  and  Baeslack,  exposed  three  tumors  to  39°  C.  for  twenty 
minutes,  but  without  being  able  to  observe  any  increase  in  their 
capacity  for  growth. 

Exposure  to  a  temperature  of  44°  C,  according  to  MichaeHs,^  favored 
the  growth  of  tumor  fragments.  Furthermore,  as  Hertwig  had  shown 
that  sea-urchin  eggs  subjected  to  the  action  of  a  narcotic  developed 
irregularities  in  their  division  figures,  and  v.  Hansemann  had  described 
irregular  mitoses  in  the  cells  of  maUgnant  growths,  Michaelis  investi- 
gated the  action  of  chloral  hydrate  upon  the  cells  of  a  mouse  tumor, 
and  found  that  in  weak  solution  it  increased  their  growth  power. 

TECHNIC    OF   INOCULATION 

The  methods  generally  employed  for  inoculating  a  tumor  have  been 
to  inject  it  with  a  syringe  or  a  Pasteur  pipette  after  reducing  it  to 
an  emulsion,  or  to  break  it  into  small  fragments  and  inoculate  these 
with  a  hollow  needle.  Jensen  ^  tried  both  of  these  plans,  and  thought 
that  the  results  of  the  latter  were  more  rehable. 

At  the  Pasteur  Institute,  where  the  two  methods  have  been  em- 
ployed in  Borrel's  laboratory,  both  Haaland  ^  and  Bridre  ^  found  that 
the  results  following  the  needle  method  were  the  more  satisfactory. 

^  Jotir.  Exp.  Med.,  1906,  viii,  486. 

British  Med.  Jour.,  1906,  ii,  1548. 
^  Zeiischrift  f.  Krebsforsch.,  1907,  v,  66.  ^  Zeitschrift  f.  Krebsforsch.,  1907,  v,  194. 

^  Centralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1903,  xxxiv,  124. 
^  An?i.  de  VInst.  Past.,  1905,  xix,  187.  ^  Ann.  de  I'Inst.  Past.,  1907,  xxi,  762. 


X 


m^ 


e> 


O 


Small  mincing  machine  devised  by  Haaland  for  emulsifying  firm  tumors.     Natural  size. 


JJI 


|N     LUERaPAP.IS 


|TJ  .  S.C.B.g 


15!     \jJ 


\l'-glass  syringe  of  0.5  cubic  centimeter  capacity  and  graduated  to  o.oi  cubic  centimeter,  employed 
to  inoculate  accurate  doses  of  tumor  emulsion.     Four-fifths  natural  size. 


Hollow  platinum-iridium  needle  for  the  inoculation  of  intact  tumor  fragments.     Natural  size. 


THE    TRANSPLANTED    TUMOR  69 

In  Ehrlich's  institute/  on  the  other  hand,  the  emulsion  method  has 
been  found  preferable,  and  the  technic  there  employed  was  de- 
scribed as  follows.  The  mouse  bearing  the  tumor  for  inoculation  is 
decapitated  with  scissors,  placed  in  alcohol-subhmate,  and,  having 
been  rinsed  off  in  alcohol,  is  laid  out  on  a  board  freshly  cleansed  with 
subHmate  solution.  The  tumor  is  removed  with  sterile  instruments, 
chiefly  by  blunt  dissection,  minced  with  scissors  and  forceps,  and  then 
broken  down  in  a  mortar  into  an  emulsion  without  the  addition  of 
any  extraneous  fluid.  Inoculation  is  done  with  capillary  pipettes 
carrying  a  stopper  of  cotton  wadding  at  the  mouth  end,  the  pipette 
being  entered  at  a  point  over  the  lower  abdomen  which  has  been 
shorn  and  washed  with  alcohol,  and  the  emulsion  deposited  in  the 
axilla.     Absolute  asepsis  must  accompany  all  the  steps  of  the  operation. 

For  the  more  ready  preparation  of  tumor  emulsions,  Haaland^ 
devised  a  smaU  mincing  machine  constructed  on  the  principle  of  the 
ordinary  meat  grinder. 

In  Bashford's  laboratory^  both  needle  and  syringe  have  been  em- 
ployed. Of  the  two  methods,  that  in  which  small  fragments  of  tumor 
were  introduced  intact  by  means  of  a  hollow  needle  was  preferred,  for 
the  reason  that  it  caused  less  damage  to  the  tumor  cells,  a  fact  which 
explained  the  superiority  of  the  results  achieved.  Although  ac- 
curate doses  could  be  administered  by  means  of  this  method 
under  certain  conditions,  the  EngHsh  workers,  reflecting  on  the  dis- 
similar results  obtained  in  various  laboratories,  felt  the  necessity  for 
a  method  which  would  permit  of  more  uniform  dosage  without 
serious  damage  to  the  cells.  The  following  procedure  was  accordingly 
adopted.  After  removal  the  tumor  was  reduced  to  an  emulsion, 
which  in  the  case  of  firm  tumors  was  most  conveniently  effected 
with  Haaland's  mincing  machine,  although  softer  growths  could  be 
emulsified  by  repeatedly  clipping  them  with  sharp  scissors.  The 
Pasteur  pipette,  which  did  not  permit  of  accurate  dosage,  was  replaced 
by  a  small  all-glass  syringe  of  0.5  cubic  centimeter  capacity,  cali- 
brated to  ox»i  cubic  centimeter.  A  hypodermic  needle  of  sHghtly 
wider  bore  than  that  used  in  a  serum  syringe  was  fitted  to  the  nozzle, 

1  Arb.  a.  d.  Konigl.  Inst.  f.  Exp.  Tlierap.,  1906,  Heft  i,  79. 

2  Bed.  klin.  Woch.,  1907,  xliv,  714. 

^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  267. 


70  THE    TRANSPLANTED    TUMOR 

and  the  injections  were  made  in  the  axillary  region  or  along  the  flank 
by  introducing  the  needle  into  the  groin,  pushing  it  toward  the  axilla, 
and  injecting  the  emulsion  during  withdrawal.  Between  injections 
the  needle  was  wiped  carefully  on  a  pledget  of  sterile  cotton-wool 
moistened  with  absolute  alcohol.  It  was  unnecessary,  except  in  special 
cases,  to  epilate  the  site  of  inoculation,  although  it  might  with  advan- 
tage be  moistened  with  alcohol. 

With  a  hollow  needle,^  the  dose  could  be  varied  between  0.005  ^^^ 
0.03  gram. 

Bashford,  Murray,  Haaland,  and  Bowen  ^  recorded  that  the  doses 
used  by  them  in  many  thousands  of  experiments  varied  between 
0.005  and  0.03  gram  where  a  tumor  fragment  was  inoculated  by  means 
of  a  needle,  and  between  0.025  ^^^  o-^S  cubic  centimeter  where  an 
emulsion  was  injected  with  a  syringe.  While  practically  all  sponta- 
neous mammary  tumors  of  the  mouse  could  be  induced  to  grow  by 
inoculating  large  numbers  of  young  animals  with  small  intact  frag- 
ments, the  number  yielding  a  successful  result  was  much  smaller 
when  0.05  to  o.i  cubic  centimeter  of  tumor  emulsion  had  been  in- 
oculated. 

The  foregoing  authors,  therefore,  as  well  as  Murray^  and  Gierke,^ 
were  of  the  opinion  that  variations  in  success  were  to  be  explained  by 
technical  differences,  pointing  out  that  the  conversion  of  a  tumor  into 
an  emulsion  involved  considerable  mechanical  injury  to  the  paren- 
chyma, and,  furthermore,  that  the  inevitable  absorption  of  part  of 
a  large  dose  of  emulsion  might  readily  be  responsible  for  the  evolution 
of  sufficient  acquired  immunity  to  prevent  the  estabHshment  of  the 
tumor. 

According  to  Bashford  ^  the  optimum  conditions  of  transplantation 
for  different  strains  could  only  be  reached  after  trial  and  error  more 
or  less  prolonged.     Most  tumors  were  best  transferred  by  the  frag- 

1  These  platinum-iridium  needles  are  provided  with  plungers  which  fit  closely  enough 
to  allow  the  tumor  fragment  to  be  aspirated  by  negative  pressure  upon  their  withdrawal. 
The  needles  are  sterilized  between  inoculations  by  being  flamed  off  with  alcohol.    (W.  H.  W.) 

^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  269. 

'  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  105. 

*  Beitrdge  zur  path.  Anat.,  etc.,  (Ziegler),  1908,  xliii,  332. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  119. 

^Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1911,  137. 


THE   TRANSPLANTED   TUMOR  7 1 

ment  method,  and  some  could  be  propagated  continuously  only  by 
this  means.  Others,  again,  gave  consistently  better  results  when 
larger  doses  of  emulsion  were  inoculated.  The  intervals  between 
successive  transplantations  were  of  great  importance,  for  while  some 
tumors  could  be  cultivated  only  by  rapid  passage,  in  the  case  of  others 
this  was  unsuitable.  The  influence  of  short  intervals  was  particularly 
noticeable  in  the  frequent  experience  that  rapid  passage  might  lead 
to  a  temporary  exhaustion  of  the  tumor  cells,  from  which  they  could 
recover  only  after  a  prolonged  sojourn  in  one  animal.  It  was  not 
always  the  most  rapidly  growing  tumors  that  could  be  transplanted  at 
the  shortest  intervals,  and  a  permanent  improvement  in  the  rate  of 
growth  and  the  inoculation  percentage  might  merely  indicate  that 
the  optimum  interval  for  grafting  had  been  selected,  either  deliber- 
ately or  accidentally. 

Other  means  of  implantation  have  been  employed,  although  less 
extensively.  Thus  Hertwig  and  Poll,^  as  well  as  Stahr,^  imbedded 
fragments  in  small  incised  wounds  which  were  sutured  afterward  with 
silk.  In  Gaylord's  laboratory  the  method  preferred  was,  as  described 
by  Clowes,^  emulsification  of  the  tumor  in  a  mortar  with  the  addition 
of  salt  solution  and  removal  of  the  connective  tissue  residue  by  means 
of  fine  rakes. 

Relative  Importance  of  Soil  and  Graft 

It  was  found,  however,  that  in  spite  of  the  most  careful  technic, 
transplantatj^on  was  not  always  successful,  and  that  in  some^animals 
the  tuniorj:ells,  unable  to  proliferate,  underwent  final  absorption. 

Thus  Jensen  *  had  attempted  the  transplantation  of  several  tumors 
before  he  succeeded  in  getting  one  to  develop,  and  Borrel  ^  found  that 
even  those  growths  which  could  be  successfully  transferred  might 
yield  but  about  io^^of_daughter  tumors. 

Ehrlich^  wrote  that  only  a  small  proportion  of  spontaneous  tumors 
were  propagable,  and  that  of  one  hundred  and  eight  such  growths 

1  Ahhandl.  d.  Konigl.  Preiiss.  Akad.  d.  Wisseiischaften,  1907,  6. 

^  Centralbl.  f.  allg.  Path.,  etc.,  1909,  xx,  869. 

^  British  Med.  Jour.,  1906,  ii,  1549. 

*  Centralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1903,  xxxiv,  29. 

^  Ann.  de  I'lnst.  Past.,  1903,  xvii,  112. 

^  Zeitschrift  f.  Krebsforsch.,  1907,  v,  61. 


72  THE   TRANSPLANTED   TUMOR 

only  about  8  %  had  been  cultivated  continuously.     The  hemorrhagic 
cyst-adenomata  seemed  to  resist  all  efforts  at  transplantation. 

Bashford,  Murray,  and  Cramer/  however,  succeeded  in  trans- 
planting hemorrhagic  tumors,  and  ascribed  their  success  to  the  fact 
that  they  had  implanted  small  fragments  into  a  large  number  of  mice 
instead  of  inoculating  large  doses  into  a  few  animals. 

But  even  though  the  most  suitable  dose  be  chosen  the  outcome  is 
still  uncertain,  for  it  is  determined  not  alone  by  the  power  of  the 
malignant  cell  to  proliferate  in  a  strange  host.  Another  condition  for 
continuous  growth  is  that  the  new  animal  shall  offer  a  proper  soil. 

Loeb^  found  that,  as  a  general  rule,  when  two  tumor  fragments 
were  transplanted  into  a  rat,  either  both  of  them  grew  or  else  neither 
one  did,  and  this,  he  thought,  indicated  differences  in  the  soil  rather 
than  in  the  grafts  introduced. 

The  relative  importance  of  these  two  factors  was  investigated  also 
by  Bashford,  Murray,  and  Cramer,^  who  inoculated  the  members  of 
one  group  of  mice  with  a  single  graft  each  and  those  of  a  second  series 
each  with  five  fragments  of  tumor.  If  idiosyncrasy  of  individual 
mice  alone  determined  whether  a  tumor  would  grow  or  not,  the  per- 
centage of  success  per  animal  should  be  the  same  in  both  series,  with 
multiple  tumors  in  the  successful  cases ;  but  the  series  with  multiple 
inoculations  gave  a  higher  percentage  of  success  than  those  with . 
single  implantations.  The  authors  accordingly  attributed  a  minor 
importance  to  the  influence  of  the  soil  in  determining  success  or 
failure,  and  a  much  greater  to  the  introduced  cells.  This  decision 
received  additional  support  from  the  constancy  with  which  different 
sporadic  tumors  gave  a  uniformly  low  percentage  of  success  or  even 
completely  negative  results,  while  others  .yielded  a  much  higher 
outcome  in  most  cases.  The  authors  were  driven  to  the  same  conclu- 
sion by  the  subsequent  behavior  of  the  different  descendants  of  one 
and  the  same  tumor,  when  one  series  grew  quickly  and  another  slowly, 
with  high  and  low  percentages  of  success,  especially  since  this  result 
might  be  reversed  in  subsequent  series.     Even  more  remarkable  was 

1  Proc.  Roy.  Soc,  Series  B,  1907,  Ixxix,  170. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  321. 
^  Jour.  Med.  Research,  1902,  N.S.,  iii,  58. 
^  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  51. 


THE   TRANSPLANTED   TUMOR 


73 


the  disparity  sometimes  seen  between  two  tumors  arising  alongside 
each  other  and  derived  from  separate  groups  of  cells  at  a  single  in- 
oculation, one  growing  quickly  and  the  other  slowly.     These   same' 
characters  were  again  presented   by  the  daughter  tumors  which  oc- 
curred when  the  two  growths  were  transplanted  into  new  mice. 

Importance  of  Uniform  Dosage 

The  importance  of  accurate  dosage  was  first  suggested  by  Loeb/ 
emphasized  later  by  Clowes  and  Baeslack,^  and  Gaylord  and  Clowes,^ 
and  has  been  upheld  consistently  by  Bashford  and  his  colleagues. 


Fig.  2. —  Diagram  illustrating  the  effect  on  the  amount  of  tissue  produced  of  increase 
in  the  number  of  cells  introduced  or  surviving  after  transplantation  (effective  initial 
dose),  under  conditions  where  the  arithmetical  factor  alone  is  assumed  to  be  of  moment. 

Thus:  ^  "The  size  the  tumours  of  any  one  strain  attain  in  a  given  time 
is  in  part  determined  by  the  proportion  of  the  introduced  cells  which 
adapt  themselves  to  the  new  conditions :  i.e.  by  the  size  of  the 
effective  initial  dose.  -  That  this  is  the  case  can  .be  demonstrated  by 
experiments  in  which  the  initial  dose  of  tumour  material  varies. 

^Jonr.  Med.  Research,  1902,  N.S.,  iii,  59. 

"^  Med.  News,  1905,  Ixxxvii,  970. 

^Surgery,  Gynecology,  and  Obstetrics,  1906,  ii,  634. 

^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  273  et  S3q. 


74  THE    TR.A.XSPLAXTED    TUMOR 

'■'The  simplest  phenomenon  is  encountered  in  the  experiments 
with  tumours  which  grow  \\-ith  a  rapidity  proportional  to  the  initial 
dose  introduced.  A  transplantable  spindle  cell  sarcoma  of  the  rat, 
for  which  we  are  indebted  to  Professor  Jensen,  illustrates  the  subject 
now  under  discussion  in  a  diagrammatic  manner.  .  .  .  The  size 
attained  by  the  tumours  in  the  animals  inoculated  \Yith.  the  larger 
dose.^  at  the  end  of  ten  days,  and  their  subsequent  progress,  present 
a  striking  contrast  to  those  of  the  tumours  arising  from  the  small  dose. 
They  are  nearly  twenty  times  as  large,  and  the  animals  succumb  more 
quickly.  It  is  important  to  note  that  the  initial  percentage  of  successes 
is  the  same  in  both  series,  viz.  loo  per  cent.   ... 

■'"WTien  experiments  with  these  doses  are  made  with  other  tumours, 
and  especially  ^^dth  transplantable  mouse  carcinomata.  the  same 
result  is  rarely  obtained.  .  .  .  Half  the  mice  ...  of  this  experi- 
ment"' ("inoculation  sviih  a  squamous  ceU  carcinoma)  "were  inocu- 
lated A^dth  0.025  c.c.  of  tumour  emulsion,  and  the  other  half  .  .  . 
with  0.15  c.c.  of  the  same  material.  An  initial  proliferation  took 
place  in  ah.  but  although  the  doses  were  as  i  :  6,  the  sizes  of  the 
tumours  arising  from  the  larger  doses  are  only  in  a  few  instances 
greater  than  those  originating  from  the  small  doses,  and  even  then 
little  more  than  t^^dce  as  large.  .  .  . 

'"Similar  experiments  i^dth  many  tumours  show  that  the  contrast 
between  the  results  of  inoculation  of  large  and  small  doses  are  often. 
the  reverse  of  those  which  we  have  been  considering  so  far.  .  .  . 
This  is  the  most  usual  result  when  mice  are  inoculated  vdih  large 
and  smaU  doses.  SmaU  doses  grojwjprogressively  and  well,  whereas 
large^doses,  even  when  followed  by  a  mor^j)ronouncedj3roliferation, 
give  tumours  which  remain  stationary  or  disappear  spontaneouslv. 
The  natural  resistance  of  the  mice  cannot  be  invoked  to  explain  the 
anomaly.  .  .  . 

'•'The  different  behaviour  of  the  tumours  arising  from  larger  and 
smaU  doses,  and  the  temporary  diminution  in  size  or  disappearance 
after  initial  prohferation.  must  be  referred  to  the  effects  of  the  absorp- 
tion of  more  or  less  tumour  material,  inducing  an  adequate  specific 
resistance  of  the  animals  in  the  one  case  and  not  in  the  other.  The 
nature  of  the  difference  between  tumours  which  support  transplanta- 
1  The  doses  employed  v,-ere  0.2  c.c.  and  o.oi  c.c.  of  an  emulsion.     (W.  H,  W.J 


THE    TRANSPLANTED    TUMOR 


75 


tion  by  large  doses,  and  those  which  do  not,  is  by  no  means  clear.  It 
is  not  merely  a  difference  in  capacity  for  independent  life  of  the  cells. 
.  .  .  The  strength  of  the  specific  resistance  following  absorption  of  the 
same  quantities  of  different  tumours  seems  to  vary  from  one  strain 
to  another,  as  does  also  the  susceptibility  of  the  tumour  cells  to  such 
altered  resistance,  and  it  is  obvious  that  differences  of  this  kind  will 
manifest  themselves  also  by  varying  susceptibiHty  to  dosage. 

"This  process,  which  may  be  described  as  a  concomitant  active 
immunization,  is  in  part  responsible  for  the  low  percentage  of  success 
attending  the  primary  transplantations  of  sporadic  tumours.  The 
ratio  of  absorbed  tissue  in  them  is  higher,  and  the  initial  prohferation 
is  less,  in  conformity  with  the  failure  of  adaptabihty.  This  effect 
is  exaggerated  when  primary  transplantation  is  carried  out  with 
large  doses,  and  is  diminished  when  minute  grafts  are  introduced. 
Where  mice  are  naturally  resistant  to  the  tumour  inoculated,  con- 
comitant immunization  greatly  enhances  it." 

In  a  paper  by  Bashford,  Murray,  and  Haaland,^  there  were  described 
two  experiments  with  the  same  tumor  strain,  in  one  of  which  pro- 
gressively growing  tumors  were  obtained  from  0.05  cubic  centimeter 
of  tumor  emulsion,  but  not  from  o.i  cubic  centimeter.     In  the  second, 


large  doses  of  emulsion  (oT5~~cubic  centimeter)  gave  a  higher  per- 
centage of  more  quickly  growing  tumors  than  did  simultaneous  inocu- 
lation of  similar  mice  with  a  small  dose  (0.025  cubic  centimeter). 
The  explanation  of  this  different  behavior  at  different  times  was,  the 
authors  thought,  to  be  sought  in  alternations  of  the  biological  quaHties 
of  the  tunior  cells  and  corresponding  alternations  in  their  vulnerability 
to  unfavorable  environment. 

Equal  emphasis  was  given  in  this  paper  to  the  importance  of  accu- 
rate dosage  when  tumors  or  normal  tissues  were  used  to  produce  the 
resistant  state. 

An  amount  of  material  much  less  than  the  smallest  dose  mentioned 
in  the  preceding  paragraphs  may  give  rise  to  a  tumor.  Uhlenhuth, 
Haendel,  and  Steffenhagen  ^  described  an  experiment  in  which  growth 
took  place  after  the  Jensen  rat  sarcoma  had  been  rubbed  into  a  scarified 
area  in  the  skin,  and  another  in  which  this  growth  was  transferred 

1  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  364. 
^  Arb.  a.  d.  Kaiserl.  Gesundheilsamte,  191 1,  xxxvi,  477. 


76  THE   TRANSPLANTED   TUMOR 

through  the  medium  of  a  pin  which  had  been  plunged  into  it  and  after- 
ward inserted  under  the  skin  of  a  healthy  rat  and  immediately  with- 
drawn. These  results  led  them  to  try  the  transmission  of  tumors 
through  the  bites  of  bed  bugs,  stinging  flies  (Stomoxys),  and  leeches, 
but  of  six  trials  with  bed  bugs  and  fhes  and  an  equal  number  with 
leeches,  not  one  was  successful. 

Importance  of  Uniform  Soil 

The  desirability  of  using  mice  of  the  same  age  and  race  was  pointed 
out  almost  coincidently  by  Bashford,  Murray,  and  Bowen,^  and  by 
Clowes  and  Baeslack.^  The  former  authors,  having  observed  differ- 
ences in  the  suitabiHty  of  animals  of  different  colors,  even  among  the 
ordinary  English  tame  mice,  were  convinced  of  the  necessity  of  using 
the  same  race  throughout  any  one  experiment.  The  wild  mouse, 
they  thought,  would  probably  offer  more  uniform  conditions  than 
the  tame  mouse,  but  a  sufficient  stock  of  uniform  age  was  difficult 
to  obtain  and  supervise.  Besides  having  the  mice  of  the  same  race 
it  was  important  that  they  should  be  of  the  same  age,  preferably 
from  five  to  seven  weeks  old.  When  the  indicated  precautions  were 
observed,  the  individual  variations  in  the  general  suitability  of  dif- 
ferent mice  of  the  same  race  and  age  were  negUgible,  if  implantation 
were  performed  at  the  same  site,  and  provided  sufficiently  large  num- 
bers of  animals  were  used. 

Inoculation  Site 

In  Bashford's  laboratory,^  the  subcutaneous  tissue  of  the  back  was 
at  first  elected,  attempts  to  perform  collateral  series  of  intraperitoneal 
inoculations  having  been  abandoned  owing  to  the  frequency  with 
which  growth  within  the  peritoneum  occurred  secondarily  from  tissue 
implanted  in  the  abdominal  muscles.  The  axilla  was  finally^  chosen, 
however,  as  the  most  suitable  location  for  the  following  reason:   ''On 

1  Proc.  Roy.  Soc,  Series  B,  1906,  Ixxviii,  196. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  285. 

2  Jour.  Exp.  Med.,  1906,  viii,  484. 

3  Proc.  Roy.  Soc,  Series  B,  1906,  Ixxviii,  197. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  286. 
*  Proc.  Roy.  Soc,  Series  B,  1967,  Ixxix,  175. 
Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  327. 


THE   TRANSPLANTED   TUMOR  77 

a  series  of  1 1  passages,  it  was  found  that  the  axilla  was  invariably  a 
more  suitable  site  than  the  dorsal  subcutaneous  tissue :  59  mice  out 
of  286  developed  tumours  both  back  and  front,  18  mice  had  tumours 
only  on  the  back,  and  59  only  on  the  front.  .  .  .  The  most  nat- 
ural explanation  of  the  difference  would  seem  to  be  that  the  con- 
nective tissue  reaction  .  .  .  without  which  the  grafts  cannot  grow, 
is  more  readily  supplied  by  the  connective  tissue  of  the  mammary 
region." 

EhrHch^  also  preferred  the  axilla,  and  routine  inoculations  were 
always  made  in  that  location. 

Implantation  has  been  undertaken  in  still  other  locations,  as,  for 
example,  successfully  in  certain  of  the  intra-abdominal  organs  by 
Goldmann,^  and  with  indifferent  success  in  the  testicle  by  Flexner  and 
JobKng.^ 

Interval  after  which  Growth  becomes  Apparent 

When  implantation  has  been  successful  a  tumor  appears  at  the 
inoculation  site  after  a  certain  period,  which  was  set  by  Jensen^  at 
about  fourteen  days,  or  in  exceptional  cases  six  to  eight  days. 
Borrel  ^  found  small  nodules  after  from  twelve  to  twenty  days,  Clowes 
and  Baeslack^  after  two  to  four  weeks,  and  Michaelis^  stated  that  one 
could  tell  by  about  the  third  week  whether  an  inoculation  had  been 
successful  or  not,  although  occasionally  the  nodule  might  not  be 
palpable  until  more  than  two  months  after  implantation.  Still,  the 
appearance  of  the  tumor  may  occasionally  be  delayed  for  as  long 
as  five  and  a  half  months,^  eight  months  as  described  by  Bridre,^  or 
even  between  eight  and  ten  months  as  recorded  by  Stahr.^° 

^  Arh.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  79. 

^  Arb.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  79  (footnote). 

^Monographs  on  Medical  and  Allied'  Subjects,  Rockefeller  Institute,  New  York,  1910, 
No.  I,  35. 

*  Centralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1903,  xxxiv,  125. 

^  Ann.  de  VInst.  Past.,  1903,  xvii,  113. 

8  Med.  News,  1905,  Ixxxvii,  968. 

'  Med.  Klin.,  1905,  i,  204. 

^  Oral  communication  regarding  a  sarcoma  of  the  rat,  by  Dr.  J.  A.  Murray  of  the  Im- 
perial Cancer  Research  Fund,  London. 

^  Ann.  de  VInst.  Past.,  1907,  xxi,  762. 

1"  Centralbl.f.  allg.  Path.,  etc.,  1909,  xx,  874. 


78  THE    TEANSPLANTED    TUMOR 

It  is  essential  to  distinguish  early  tumors  from  inflammatory  swell- 
ings, as  has  been  pointed  out  by  Clowes  and  Baeslack/  Bashford, 
Murray,  and  Cramer,^  and  Michaelis.^  In  the  experiments  of  Clowes 
and  Baeslack,  inflammatory  swelKngs  frequently  occurred  soon  after 
inoculation,  but  differed  from  malignant  tumors  either  by  undergoing 
absorption  or  by  ulcerating  out  in  the  course  of  two  or  three  weeks. 
A  true  tumor,  on  the  other  hand,  developed  somewhat  later  and  was 
generally  firmer  than  an  inflammatory  mass. 

Inoculation  of  Stationary  or  Receding  Tumors 

Loeb  ^  removed  half  of  a  stationary  tumor  from  a  rat  and  re-im- 
planted it  in  the  same  animal,  after  which  both  the  new  graft  and  the 
remaining  piece  began  to  grow  at  a  rapid  rate.  In  this  case  it  was  sug- 
gested that  the  liberation  of  the  tumor  from  the  tension  of  its  capsule 
might  have  permitted  the  resumption  of  proliferation.  A  fragment 
taken  from  a  growth  actually  diminishing  in  size  grew  so  weE  after 
inoculation  into  another  rat  that  a  number  of  tumors  were  after- 
ward transplanted  from  it.  The  original  tumor,  however,  continued 
to  recede  until  only  a  few  small  nodules  were  left. 

White  and  Loeb^  later  entered  more  fully  into  this  question  and 
found  that,  in  general,  the  tumors  resulting  from  the  transplantation  of 
stationary  or  receding  growths  did  not  have  a  proHferative  activity 
equal  to  those  descended  from  vigorously  growing  tumors. 

In  the  opinion  of  Bashford,  Murray,  and  Bowen,^  diminished  trans- 
plantabihty  was  due  to  a  real  alteration  in  the  parenchymal  cells,  an 
inabihty  to  establish  themselves  in  new  hosts,  coinciding  with  the 
spontaneous  cessation  of  proliferation  in  an  animal  in  which  growth 
had  already  become  established. 

1  Med.  News,  1905,  Ixxxvii,  968. 

2  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  63  (footnote). 

3  Med.  Klin.,  1905,  i,  204. 

*  Jour.  Med.  Research,  1901,  N.S.,  i,  34. 

Arch.f.  path.  Anat.,  etc.,  (Virchow),  1902,  clxvii,  175. 

Jour.  Med.  Research,  1902,  N.S.,  iii,  47. 
5  Centralhl.f.  Baki.,  etc.,  erste  Abt.,  Orig.,  1910,  Ivi,  488. 
^  Proc.  Roy.  Soc,  Series  B,  1906,  Ixxviii,  208. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  299. 


THE   TRANSPLANTED   TUMOR  79 

Transplantation  of  Metastases 

The  lung  metastases  of  four  spontaneous  tumors  were  transplanted 
by  Murray/  with  success  in  two  cases. 

Uhlenhuth  and  Weidanz-  also  attempted  the  transplantation  of 
pulmonary  metastases,  but  their  mice  died  of  sepsis  before  the  comple- 
tion of  the  experiment.  A  somewhat  more  encouraging  issue  attended 
their  endeavors  to  cultivate  lymph  node  metastases,  and  one  tumor  was 
obtained  among  four  inoculations.  Unfortunately,  however,  the  mice 
into  which  this  growth  was  implanted  died  of  mouse  typhus  before  the 
experiment  was  finished. 

Gay^  was  successful  in  transplanting  metastases  of  the  Flexner- 
Jobhng  rat  carcinoma,  and  ventured  the  opinion  that  there  occurred 
after  several  generations  an  increase  in  the  virulence  of  the  resulting 
tumors  which  was  exemplified  by  a  greater  proliferative  activity  and 
the  production  of  wider  spread  metastases  of  a  more  pronounced  epi- 
thelial type. 

Inoculation  of  Tumor  Mixtures 

Mixtures  of  tumors  have  been  transplanted  in  a  few  instances. 
Apolant  and  Ehrlich"*  recorded  a^  series  of  inoculations  with  a  mixture 
of  three  alveolar  carcinomata  and  one  malignant  adenoma,  in  which 
the  first  generations  showed  no  departure  from  the  structure  of  an 
ordinary  transplantable  alveolar  carcinoma.  Sarcoma  development 
occurred  in  this  strain  between  the  twelfth  and  fourteenth  generations. 

Haaland  ^  mixed  Jensen's  carcinoma  with  a  sarcoma  from  Ehrhch's 
laboratory,  and  obtained  the  carcinomatous  strain  pure  again  in 
Danish  mice  and  the  sarcomatous  in  Berlin  mice.  The  Danish  mice 
were  susceptible  to  carcinoma  and  refractory  to  sarcoma,  while  the 
Berhn  strain  was  highly  susceptible  to  sarcoma  and  resistant  to  Jen- 
sen's carcinoma. 

Ehrlich^  and  Apolant''  described  the  results  following  the  trans- 

*  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  106. 

^  Arb.  a.  d.  Kaiserl.  Gesiuidheitsamte,  1909,  xxx,  441. 

^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1908-1909,  vi,  74. 

^  Berl.  klin.  Woch.,  1906,  xliii,  38.  ^  Bcrl.  klin.  Woch.,  1907,  xliv,  716. 

^  Zeilschrifl  f.  Krebsforsch.,  1907,  v,  67.    ''  Zcitschrift  f.  Krebsforsch.,  1907-1908,  vi,  251. 


8o  THE    TR.1XSPLAXTED    TUMOR 

plantation  of  mixtures  of  carcinoma  and  sarcoma,  carcinoma  and 
chondroma,  and  chondroma  and  sarcoma.  ]\Iixed  tumors  in  which 
both  components  were  intermingled,  and  which  were  exactly  analogous 
to  the  carcinoma  sarcomatodes  of  v.  Hansemann,  were  readily  ob- 
tained by  the  inoculation  of  a  mixture  of  sarcoma  and  carcinoma.  It 
was  much  more  difficult  to  produce  a  mixed  tumor  with  combinations 
of  chondroma  and  carcinoma,  or  sarcoma,  because  the  elements  varied 
so  much  in  \'itahty  and  in  prohferative  energ}'  that  pure  chondromata, 
carcinomata,  or  sarcomata,  were  usually  the  outcome  of  the  experiment. 
But  even  when  both  components  grew  there  was  never  the  intimate 
comminghng  which  would  allow  one  to  claim  the  production  of  a  dis- 
tinct new  variety  of  tumor,  for  both  remained  isolated  and  each  one 
produced  its  o"«ti  t}^ical  form  of  neoplasm.  It  had  been  found  that 
the  inoculation  yield  was  much  less  affected  by  low  degrees  of  tempera- 
ture  than  was  the  proliferative  energ^^  and  yet  when  sarcoma  that 
had  been  exposed  to  —  lo"^  C.  for  periods  even  as  long  as  nineteen 
days  was  inoculated  together  mth  chondroma,  it  was  impossible  to 
produce  a  mixed  tumor  with  an  equal  distribution  of  the  two  com- 
ponents. There  occurred  merely  two  independent  tumor  tissues  grow- 
ing side  by  side  ^  never  an  amalgamation  into  a  distinct  new  tApe. 
The  importance  of  these  experiments  for  general  pathology  lay  in  the 
demonstration  that  a  mixed  tumor  could  result  or  persist  only  when 
the  biological  conditions  of  growth  for  the  two  components  were 
approximately  equal. 

Resistance  Offered  by  the  Cancer  Cell  to  Various  Agents 

Jensen^  discovered  that  no_growth  followed  the  inoculation  of 
crushed  cells,  and  that  the  resistance  which  the  cancer  cell  was  able 
to  oppose  toward  various  injurious  agents  AA'as  perhaps  somewhat 
lower  than  that  displayed  by  the  cells  of  normal  tissue.  \\'liile  his 
tumor  was  still  capable  of  successful  transplantation  after  an  exposure 
of  about  eighteen  days  to  a  temperature  of  i°  to  3°  C.  and  of  about 
twelve  days  to  room  temperature,  it  remained  ahve  hardly  twenty- 
four  hours  if  kept  at  body  heat.  When  warmed  for  five  minutes  at 
47°  C,  or  cooled  for  a  few  minutes  at  —  20°  C,  the  tumor  was  killed. 

1  Centralbl.f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1903,  ssxiv,  129,  131. 


THE    TRANSPLANTED    TUMOR  8 1 

Intense  light  (Finsen) ,  in  so  far  as  it  was  able  to  penetrate  the  tissiie^ 
was  fatal,  and  partial  drying,  or  a  five^minute  exposure  to  a  -  j  %^ 
solution  of  carbolic  acid,  also  rdDbed  the  cells  of  their  power  to  pro- 
Uferate. 

Loeb^  investigated  the  maximum  temperature  to  which  a  rat  sar- 
coma could  be  exposed  without  losing  its  power  to  grow.  He  found  that 
fragments  kept  at  43^  to  44°  C.  for  forty  minutes  remained  viable,  as 
did  one  heated  for  twenty-five  minutes  at  43°  C.  and  then  for  fifteen 
minutes  at  45°  C.  On  the  contrary,  pieces  exposed  for  thirty  minutes 
to  a  temperature  of  45°  C.  as  well  as  those  exposed  for  a  similar 
length  of  time  to  still  higher  degrees  (up  to  50°  C),  did  not  grow  in  any 
single  instance.  Fragments  of  tumor  kept  on  ice  for  five  days  were 
successfully  transplanted,  and  it  was  thus  clear  that  the  tumor^pro- 
ducing  factor  did  not  materially  lose^n  power  after  having  been  kept 
for  this  length  of  time  at  a  temperature  of  from  2°  to  4°  C.  That 
intact  cells  were  necessary  for  growth  was  demonstrated  by  the  neg- 
atiye  result  which  attended  the  in]'e£tiQiLQ|._filtered  emulsions. 

Michaelis^  achieved  a  successful  outcome  from  the  transplantation 
of  Jensen's  tumor  after  it  had  lain  in  an  ice-box  for  five  days,  and  even 
after  it  had  been  exposed  to  liquid  air  for  half  an  hour.  Chloroform 
water,  however,  robbed  the  cells  of  their  power  to_grow. 

Moore  and  Walker,^  several  years  later,  observed  that  a  half-hour's 
exposure  to  liquid_air  at  a  temperature  of  about  —  195°  C.  was  not 
always  fatal  for  cancer  cells,  wldle  Gaylord^  found  that  they  could 
withstand  this  temperature  for  eighty  minutes. 

In  the  experiments  of  Clowes,^  all  tumor  cells  seemed  to  be  destroyed 
at  45°  C.  Toward  organic  disinfectants,  hov/ever,  their  resistance 
was  very^Jiigh.  Treatment  for  an  hour  with  mercuric  .chloride  at  a 
concentration  of  1-3500  was  insufficient  to  prevent  the  development 
of  a  small  proportion  of  slowly  growing  tumors,  and  it  was  not  until  a 
strength  of  1-2000  was  reached  that  compl£te_destruction  of  the  cells 
was  effected.     They  were  killed  also  by  mercuric  iodide  in  a  solution 

^  Jour.  Med.  Research,  1902,  N.S.,  iii,  62. 

Arch.f.  path.  Anat.,  etc.,  (Virchow),  1903,  clxxii,  345. 
^  Med.  Klin.,  1905,  i,  204.  ^Lancet,  1908,  i,  226. 

*  Jour.  Inf.  Diseases,  1908,  v,  443. 
^British  Med.  Jour.,  1906,  ii,  1549. 


82  THE    TR-JlXSPLAXTED    TUMOR 

of  from  I-2000  to  1-2500  and  ammonium  fluoride  in  a  concentration 

of  i-iooo.  but  potassium  cyanide  in  an  -^—  solution  was  unable    to 

100 

effect  the  death  of  either  the  Jensen  or  the  Brooklyn  tumor,  although 

bacteria  are  entirely  destroyed  by  an  — — .  solution. 

■ '"  '  20a 

Ehrlich  ^  considered  that  the  maxima  of  temperature  giyen  by  Jensen 
and  Loeb  represented  the  maxima  for  his  o^vn  carcinomata  and  sarco- 
mata. But  the  few  minutes'  exposure  to  —20^  mentioned  by  Jensen 
as  haying  sufficed  to  destroy  his  tumor  was,  in  Ehrhch's  experience, 
not  enough,  for  he  had  often  seen  growth  power  preserved  after  ex- 
posure for  forty-eight  hours  to  a  temperature  of  from  25°  to  30°  be- 
low zero  C  and  in  one  case  he  had  been  able  to  transplant  a  carcinoma 
kept  for  two  years  at  8'  to  10^  below  zero.  In  the  case  of  a  chondroma 
he  had  been  able  to  discover  microscopic  evidence  of  temporary  growth 
in  material  heated  for  an  hour  at  50"  C.  an  exposure  which  would 
have  destroyed  the  cells  of  a  sarcoma  or  a  carcinoma,  while  a  success- 
ful result  had  attended  the  transplantation  of  a  chondroma  that  had 
been  kept  three  days  at  the  temperature  of  hquid  air.  In  these  ex- 
periments, however,  as  the  vitaUty  of  the  cells  had  been  very  seriously 
impaired,  tumors  larger  than  a  pea  were  never  obtained,  and  these 
gradually  disappeared  instead  of  gro\\ang  progressively. 

Bridre  -  found  that  mice  developed  growths  only  exceptionally 
after  the  inoculation  of,  finely  ground  tumor,  and  ne\^  after  the 
injection  of  an  emulsion  in^sahne  solution  (filtered  or  unfiltered), 
or  of  tumor  dried  or  heated  above  50°  C.  In  short,  it  was  necessary 
to  inoculate  intact  cells. 

From  the  work  of  Haaland,^  it  appeared  that  the  cells  of  a  sar- 
coma were  better  able  to  resist  heat  than  those  of  a  carcinoma,  for  he 
was  able  to  purify  a  mixed  tumor  of  its  carcinomatous  elements  by 
exposure  to  44'  C.  for  thirty-five  minutes  or  longer. 

Lewin  '^  was  able  to  substantiate  for  a  carcinoma  of  the  rat  all  the 
statements  which  had  been  apphed  to  mouse  carcinomata,  and  for  an 

^  Zeitschrift  f.  Krebsforsch.,  1907,  v,  65. 

2  Ann.  de  I'lnst.  Past.,  1907,  xxi,  767. 

3  Berl.  klin.  Woch.,  1906,  xliii,  40. 

^  Zeitschriftf.  Krebsforsch.,  1907-1908,  vi,  304. 


THE    TRANSPLANTED    TUMOR  83 

artificial  mixed  tumor  the  observation  of  Haaland  just  cited.  He 
succeeded  also  in  repressing  the  development  of  keratin  by  exposure 
to  46°  C.  for  a  quarter  of  an  hour. 

The  experiments  of  Uhlenhuth  and  Weidanz  ^  yielded  results 
quite  analogous  to  those  of  other  observers.  Tumor  cells  were  killed 
by  an  exposure  to  56°  C.  for  twenty-five  minutes,  but  not  by  being 
subjected  for  the  same  length  of  time  to  45°  C. ;  nor  was  a  several 
days'  sojourn  in  an  ice  and  salt  mixture,  at  a  temperature  far  be- 
low the  freezing  point,  fatal  to  them. 

Loeb  and  White  ^  kept  mouse  tumor  at  44°  C.  for  varying  lengths 
of  time  and  plotted  the  results  of  inoculation  in  a  series  of  curves 
depicting  the  growth  energy,  the  latent  period,  and  the  number  of 
receding  tumors.  The  curves  corresponded  rather  closely,  and  showed 
that  up  to  a  certain  temperature  the  result  was  roughly  proportional 
to  the  degree  of  heat  appHed.  In  all  the  curves  there  was  a  critical 
point  between  forty-five  and  fifty-five  minutes,  and  at  the  end  of  the 
latter  period  fundamental  alterations  in  the  cell  set  in.  The  three 
properties  above  mentioned  probably  depended,  therefore,  upon  one 
and  the  same   factor  of  the  cell  protoplasm. 

The  cancer  cell,  however,  may  be  prevented  from  growing  by  damage 
more  subtle  than  any  of  the  comparatively  gross  injuries  so  far  de- 
scribed, for  Haaland  ^  showed  that  the  a^tion^Ljadium  was  fa^al^  to 
itsjife,  although  the  anatomical  structure  remained  unaltered. 

COMPARATIVE    GROWTH   RATE    OF    THE    MALIGNANT    CELL 

While  much  has  been  written  in  the  past  about  the  enormous  pro- 
liferative capacity  of  the  cancer  cell  it  may  very  weh  be  that  such 
statements  have  been  unwarranted,  and  that  the  true  key  to  the  na- 
ture of  maHgnant  growth  Hes  in  the  direction  of  an  explanation  of  the 
contiijupus,  rather  than  the  rapid,  growth  of  the  cancer  cell.  Thus 
the  power_QfJhis_ceU^tojtnultiply  proves  but  a  sorrx_a£com^lishment 
when  compared  with  the  growth  energy  of  the  bacteria,  organisms 

1  Arb.  a.  d.  Kaiserl.  Gesundheitsamte,  1909,  xxx,  441. 

2  Centralbl.  f.  Bakt.,  etc.,  erste  .\bt.,  Orig.,  1910,  Ivi,  325. 

3  Proc.  Roy.  Soc,  Series  B,  1909-1910,  Lxxxii,  297. 
Lancet,  19 10,  i,  789. 


84 


THE    TRAXSPLAXTED    TUMOR 


which  Minot  ^  has  estimated  are  able  to  add  looo^o  to  their  original 
weight  \Aithin  a  few  hours,  while  according  to  the  same  author  the 
embryos  of  rabbits  and  other  mammals,  no  less  than  those  of  birds, 
may  be  said  with  safety  to  grow  at  least  1000%  a  dav. 

A  close  comparison  has  been  drawn  by  Bashford,-  who  weighed 
mouse  embryos  at  different  periods  of  gestation  and  estimated  the 
rate   at  which  growth   took  place   after  the  embryo  had  reached  a 


LLJl 


Fig.  3. — Diagrammatic  comparison  of  rate  of  growth  of  various  tumor  strains  on 
the  basis  of  the  number  of  days  required  to  produce  i  gram  of  tissue  from  a  meas- 
ured dose  (0.02-0.03  gram)  inoculated.  The  rate  of  growth  of  embrj^onic  tissue  is  in- 
dicated on  the  basis  that  the  mouse  embryo  weighs  0.02-0.03  gram  at  the  eleventh  day 
of  gestation  and  at  birth  1-1.5  grams. 

weight  (0.02  to  0.03  gram;  corresponding  to  the  amount  of  tumor  usually 
inoculated.  When  he  compared  the  proliferative  acti\dty  of  the  two 
tissues  it  became  CAddent  that,  while  some  tumors  might  attain  the 
rate  of  growth  possessed  by  the  embryo,  most  of  them  fell  far  below  it. 


^  The  Problem  of  Age,  Growth,  and  Death,  X'ew  York  and  London,  igo8,  12  = 
-  Fourth  Sci.  Report,  hnperial  Cancer  Research  Fund,  London,  191 1,  199. 


i: 


so- 

40 
30 

20- 

10 


500  DA>f9 


eo 
so- 


(00  2Q0  300  400  JOOOAYS 

Rise  and  fall  in  success  of  transplantation  in  four  strains  of  Jensen's  mouse  carcinoma.  The  abscissae 
represent  the  number  of  daj's  during  which  the  propagation  of  the  several  strains  was  continued. 
The  ordinates  show  the  percentages  of  success  in  consecutive  series  of  sub-inoculations.  In  each 
figure  the  curve  bifurcates  at  the  time  when  two  separate  tumors  of  the  original  strain  were  used 
to  start  new  strains.  The  time  when  growth  was  artificially  interrupted  by  transplantation  is  rep- 
resented by  points  and  crosses  for  the  two  daughter  strains  of  each  figure.  These  curves  represent 
experiments  lasting  for  nearly  500  days,  and  carried  out  upon  nearlj''  8000  mice.  The  results  of 
the  first  transplantation  of  Jensen's  tumor  into  English  mice  are  not  included. 

The  large  fluctuations  in  the  success  of  transplantation  are  similar  in  all  four  ciu-ves.  Success  is 
seen  to  increase  through  a  series  of  successive  inoculations  until  a  maximum  is  reached.  From 
this  point  onward  the  result  diminishes  until  a  minimum  is  arrived  at,  from  which  point  the  curv^e 
again  rises  to  a  maximiun.  The  general  correspondence  in  the  four  series  can  hardly  be  pure  coin- 
cidence, and  the  conclusion  appears  justified  that  the  power  to  establish  themselves  in  new  hosts 
varies  periodically  in  the  cells  of  this  tumor,  from  inherent  causes. 

The  occurrence  of  such  periodic  variations  in  the  growth  of  tumors  must  be  borne  in  mind  in 
appraising  the  value  of  therapeutic  measures. 


THE    TEANSPLANTED    TUMOR  85 

PLUCTUATIONS   IN   GROWTH  ENERGY 

When  tumor  growth  was  studied  over  long  periods  of  time  in  suc- 
ceeding series  of  mice  by  Bashford,  Murray,  and  Cramer/  it  was 
found  that :  — 

''The  experimental  propagation  of  mahgnant  new  growths  leads  to 
an  apparently  continuous  proHferation  which  is  merely  artificially 
divided  up  by  the  process  of  transference  to  successive  hosts.  The 
Hmits  of  growth  are  not  attained  in  any  one  animal,  and  transplanta- 
tion again  becomes  necessary  after  intervals  which  vary  according  to 
the  rate  of  growth  of  the  tumour  or  to  the  degree  in  which  the  animal 
suffers  from  the  presence  of  the  tumour  or  from  intercurrent  disease. 
Thus  the  time  of  transplantation  does  not  possess  the  importance  of  a 
natural  starting-point  for  the  growth  of  the  tumour  which  follows  it, 
neither  does  it  coincide  with  a  terminal  stage  of  the  growth  with  which 
transplantation  is  effected.  .  .  .  While  for  any  one  sporadic  tumour 
the  average  percentage  of  success  of  a  large  number  of  experiments  is 
fairly  constant  through  many  generations,  considerable  variations  in 
success  attend  the  inoculations  of  one  and  the  same  tumour  at  different 
times.  The  variations  in  success  are  frequently  accompanied  by  dif- 
ferences in  the  rate  of  growth  of  the  tumour  and  do  not  remain  con- 
stant for  their  descendants  in  further  transplantation.  Thus  one 
series  of  inoculations  may  give  •  a  small  percentage  of  slow-growing 
tumours  which  at  a  subsequent  period  may  begin  to  grow  rapidly,  or 
on  transplantation  while  still  growing  slowly  give  a  high  percentage 
of  quickly  growing  tumours. 

"These  variations  in  the  behaviour  of  different  sporadic  tumours, 
therefore,  indicate  differences  in  degree  rather  than  in  kind,  comparable 
to  those  which  may  obtain  in  the  different  descendants  of  the  same 
tumour.   .  .  ." 

In  addition  to  variations  in  the  histological  characters  of  trans- 
planted tumours,  gradual  fluctuations  in  the  rate  of  growth  and  per- 
centage of  success  were  found  when  the  results  of  long-continued 
experiments  were  compared. 

"These  curves  represent  experiments  lasting  for  nearly  500  days, 
and  give  the  results  obtained  on  nearly  8000  mice,  .  .  . 

^  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  48  et  seq. 


86  THE    TB_A.XSPLAXTED    TUilOR 

"The  large  fluctuations  in  the  success  of  transplantation  are  similar 
in  all  four  curves.  Success  is  seen  to  increase  through  a  series  of  suc- 
cessive inoculations  till  a  maximum  is  reached.  From  this  point  on- 
wards success  diminishes  till  a  minimum  is  arrived  at,  from  which  the 
cur\'e  again  rises  to  a  maximum.  The  fall  in  the  curves  coincided  with 
the  occurrence  of  numerous  negative  series  of  transplantations  in 
daughter  strains.  .  .   . 

"The  conclusion  appears  justified  that  the  power  of  establisliing 
themselves  in  new  hosts  varies  periodically  in  these  tumour  cells  from 
inherent  causes." 

In  a  later  paper,  Bashford,  ^Murray,  and  Bowen  ^  analyzed  more 
minutely  the  fluctuations  in  growth  energ}'.  \Mien  all  precautions 
were  taken  to  insure  accuracy  of  dosage,  similarity  of  soil.  etc..  fluc- 
tuations independent  of  these  factors  still  appeared,  and  the  authors 
beheved  that  they  were,  in  all  probabiHty.  natural  features  of  prolif- 
eration. They  repeatedly  saw  the  inoculation  percentage  rise  to  a 
maximum  which  could  not  be  maintained,  to  be  followed  by  a  fall, 
which  also  was  not  permanent.  They  had  encountered  no  exception 
to  this  rule  in  more  than  six  hundred  series  of  inoculations  -udth 
Jensen's  tumor,  and  the  rise  to  a  maximum  with  the  subsequent  fall 
had  been  repeated  fifty  times  in  simultaneous  series  of  experiments. 
Wlien  the  subsequent  beha\'ior  of  the  descendants  of  several  of  the 
daughter  tumors  from  any  one  batch  of  inoculations  was  followed, 
successive  maxima  were  seen  to  arise,  one  after  another,  at  short 
interA-als.  The  maximum  percentage  of  success  of  the  experiments 
as  a  whole,  was  maintained  continuously  at  a  high  level  between 
seventy  and  ninety.  Each  strain,  after  reaching  its  maximum,  fell 
and  made  way  for  another  which  had  pre\-iously  presented  a  lower 
percentage;  and  this  latter  feU  in  turn  after  having  attained  its 
maximum. 

The  behavior  of  the  component  parts  of  the  Jensen  tumor,  when  this 
growth  was  propagated  in  a  large  number  of  mice,  represented,  in  the 
opinion  of  the  authors,  what  might  be  regarded  as  occurring  simulta- 
neously in  different  parts  of  a  single  tumor  when  it  was  allowed  to  pro- 
liferate for  a  long  period  in  one  mouse.     After  a  time  any  single  tumor 

1  Proc.  Roy.  Soc,  Series  B,  1906,  lxx\'iii,  195. 
Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  284. 


JOAPft   JUN      JUL      AUG      SEP     OCT      NOV      OLC      JAIt  07  FLS     n>\R     APR      MAY     JUN     JUL      AUG     &EP      OCT       NOV      OLC      JMI'08  FES     MAB      API 

Percentage  curve  of  a  mammary  adeno-carcinoma  of  the  mouse.  After  a  short  period  of  depression 
the  curve  rises  rapidly  till  the  yth  generation,  and  then  falls.  A  second  and  third  rise  then  follow- 
in  two  strains  propagated  separately.     While  one  ( )  falls  again  and  then  rises  slowly  to  a 

maximum,  the  other  ( )  fluctuates  between  35  and  50  per  cent  for  9  months,  after  which 

it  also  rises. 


«? 


JAH07  F(B 


JUM  JUL 


7J«rL»4   JUL       '      *U0  itP  aCT  NOV  0 

Squamous  cell  mammary  carcinoma  of  the  mouse.     Rapid  rise  in  percentage  of  success  at  the  third 
transfer  (3  A),  followed  by  a  fall  and  a  second  rise. 


Hemorrhagic  mammary  alveolar  carcinoma.     Slight  drop,  followed  by  a  gradual  rise. 


Fluctuations  of  growth  energy  in  three  tumor  strains. 


THE   TRANSPLANTED    TUMOR 


87 


Fig.  4.  —  Fluctuations  in  growth  energy. 


could  no  longer  be  regarded  as  consisting  of  cells  with  equal  proliferative 
power,  for  just  as  a  composite  chart  of  all  the  strains  propagated  in- 
dicated their  very  different  behavior  at  any  one  date,  so,  in  any  single 
tumor,  growth  was  proceeding  actively  in  one  part  while  at  another  it 
was  going  on  slowly,  or  had  actually  ceased.  The  same  heterogeneity 
was  postulated  for  spontaneous  tumors  which,  in  all  probability,  owed 
their  apparently  continuous  growth  to  the  simultaneous  presence  in 
different  areas  of  numerous  growing  centers  which  masked  the  effects 
of  concomitant  immunization,  thus  accounting  for  the  rarity  of  spon- 
taneous absorption  among  sporadic,  as  compared  with  transplanted, 
tumors.  The  greater  frequency  with  which  growth  ceased  in  propa- 
jgated  tumors,  to  be  followed  by  spontaneous  absorption,  seemed  to  be 
due  to  the  greater  homogeneity  resulting  from  the  limited  number  of 
growth  centers  represented  in  any  one  implantation. 


88 


THE   TRANSPLANTED   TUMOR 


By  choosing  a  suitable  interval  for  inoculation  of  tumors  selected 
from  series  with  from  90  to  100  %  of  success,  and  especially  by  in- 
creasing the  dose  from  o.oi  to  0.05  gram,  Bashford,  Murray,  and 
Cramer^  were  able  to  evade  the  diminution  usually  following  each 
maximum,  for  a  considerable  number  of  transferences. 


Fig.  5. —  Graphic  record  of  propagation  through  ten  passages  of  a  single  strain  of 
Jensen's  carcinoma  in  which  success  has  not  fallen  below  85  %. 


Calkins  ^  could  not  accept  the  interpretation  of  these  fluctuations 
advanced  by  Bashford  and  his  colleagues,  and  argued  that  rhythms  of 
growth,  to  be  comparable  with  those  of  a  free  hving,  or  of  a  cleavage 
cell,  should  be  looked  for  in  the  individual  mouse  rather  than  in  succes- 
sive batches  of  mice.  Again,  curves  such  as  had  been  published  by  the 
EngHsh  school  introduced  two  factors,  one  the  percentage  of  "takes" 
and  the  other,  the  time  required  for  the  tumor  to  develop.  It  was  the 
time  factor  which  really  measured  growth  energy,  indicating  roughly, 
as  it  did,  the  rate  of  division  of  the  cells,  and  what  the  curves  of 
Bashford  had  reproduced  were  merely  recurring  alternations  of  infec- 

1  Proc.  Roy.  Soc,  Series  B,  1907,  Lxxix,  174. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  326. 

2  Jour.  Exp.  Med.,  1908,  x,  283. 


THE   TRANSPLANTED   TUMOR 


89 


tivity  (percentage  of  "takes").  Calkins  constructed  a  curve  to  repre- 
sent the  variations  in  infectiveness,  and  another  to  indicate  the  number 
of  days  required  for  the  tumors  to  reach  a  point  where  they  would 
kill  the  mice.     His  figures  showed  that  the  curves  were  by  no  means 


IK/i 
DOX 

edJ 
40;? 

ZOX 

10% 

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1 

4f) 

. 

. 

.w 

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10  > 

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Fig.  6. 


ninHysrsQffliiiHiiiMayszMZHiMixii 

-  The  waves  of  growth  described  by  Bashford  are  shown  by  the  regular 
alternations  of  infectivity,  not  in  the  line  showing  growth  energy. 


equivalent,  and  that  too  much  was  assumed  in  choosing  the  percentage 
of  "takes"  as  the  measure  of  growth  energy. 

Bashford,  Murray,  Haaland,  and  Bowen  ^  repHed  that,  as  they  had 
always  been  aware,  the  percentage  of  success  could  never  be  regarded 
as  anything  but  an  arbitrary  standard  by  which  to  measure  growth 
energy.  And  while,  in  the  comparison  of  different  strains  the  per- 
centage of  success  varied  independently  of  the  energy  of  growth,  within 
the  Hmits  of  a  single  strain  there  was  a  very  definite,  although  not  ab- 
solute, correspondence  between  them.  Either  by  measuring  the  area 
of  tumors  drawn  in  silhouette,  or  by  killing  large  numbers  of  animals  at 
regular  intervals  and  weighing  the  amount  of  tumor  produced,  it  was 
possible  to  get  a  more  correct  estimate  of  growth  energy  than  by  means 
of  the  plan  adopted  by  Calkins ;  this  was  subject  to  uncontrollable 
fallacies  because  the  death  of  the  animals  was  only  a  secondary  result 
of  growth.     Nevertheless,  the  curve  constructed  by  that  investigator 

*  Third  Sci.  Report,  It7iperial  Cancer  Research  Fund,  London,  1908,  281. 


QO  THE    TEANSPLANTED    TUMOR 

showed  that  the  higher  was  the  percentage  of  takes  the  lower  was 
the  interval  within  which  the  mice  died,  and  the  authors  were,  there- 
fore, at  a  loss  to  understand  how  he  had  come  to  a  different  conclusion. 

SPONTANEOUS    ABSORPTION 

Transplanted  tumors  which  have  become  estabHshed  may  grow  pro- 
giressively  until  they  attain  a  size  equal  to  or  even  exceeding  that  of 
the  animals  in  which  they  are  growing  or,  having  reached  a  certain 
point,  may  undergo  a  gradual  spontaneous  absorption.  Spontaneous 
absorption  may  be  entire  or  it  may  be  partial,  growth  setting  in 
again  before  complete  disappearance  has  been  effected.  A  strain 
may  exhibit  among  the  tumors  of  one  series  the  phenomena  of  unin- 
terrupted growth,  retardation  and  resumption  of  growth  or,  finally, 
spontaneous  cure.  Such  a  tumor  has  been  described  by  Bashford 
and  Russell.-^ 

Loeb  -  was  the  first  to  observe  and  to  appreciate  the  significance  of 
the  spontaneous  disappearance  of  transplantable  tumors.  The  same 
phenomenon  had  been  encountered  by  Jensen,^  but  was  attributed  by 
him  to  certain  therapeutic  experiments  then  in  progress,  erroneously, 
however,  as  he  ^  said  in  a  later  article. 

Michaelis  ^  described  three  tumors  of  the  Jensen  strain  which  had 
remained  stationary  or  receded  after  reaching  the  size  of  a  pea,  and 
Apolant,^  in  an  article  on  the  effect  of  radium  upon  mouse  carcinoma, 
wrote  that  in  two  out  of  eleven  controls  the  tumor  had  been  absorbed 
spontaneously.  Commenting  upon  the  experiment,  he  said  that  ces- 
sation of  growth,  or  even  the  entire  disappearance  of  nodules,  had 
been  observed  in  every  series,  although  in  only  a  small  percentage 
of  the  animals. 

Clowes ''  recorded  the  complete  absorption  of  Jensen's  tumor  in  at 
least  15  to  20%  of  the  cases  and,  in  a  more  detailed  article  with 

1  Proc.  Roy.  Soc,  Series  B,  1909-1910,  Lxxxii,  298. 

Lancet,  1910,  i,  784.  ''■Jour.  Med.  Research,  1901,  N.S.,  i,  34. 

^  Centralhl.  f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1903,  xxxiv,  30. 
*  Zeitschrift  f.  Krebsforsch.,  1908-1909,  vii,  281. 

5  Verhandl.  d.  Komitees  f.  Krebsforsch.,  1903-1904,!^,  38.  See  Deut.  med.  Woch.,  1904, 
XXX,  1264. 

^  Deut.  med.  Woch.,  1904,  xxx,  456. 

'  Johns  Hopkins  Hosp.  Bull.,  1905,  xvi,  130. 


THE    TEANSPLANTED    TUMOR  QI 

Baeslack,^  in  about  fifty  mice.  To  exclude  early  inflammatory  swellings 
as  a  source  of  error  the  authors  had  adopted  for  a  standard  the  ab- 
sorption, not  less  than  three  weeks  after  inoculation,  of  a  tumor  which 
had  at  some  period  reached  the  volume  of  twenty  cubic  milhmeters. 
Gaylord  and  Clowes  ^  later  described  spontaneous  recovery  in  one 
hundred  and  one  cases,  or  about  23%  of  the  inoculated  animals,  and 
con  eluded  that  the  chances  of  recovery  were  inversely  proportional  to 
the  size  of  the  tumor. 

Bashford,  Murray,  and  Cramer,^  in  their  earHer  experiments,  had 
seen  only  one  case  of  spontaneous  absorption  among  three  thousand 
Jensen  tumors  of  over  fourteen  days'  growth,  but  Bashford^  was 
later  able  to  confirm  the  findings  of  other  investigators  with  the 
statement  that  in  some  series  as  many  as  50%  of  animals  with  large 
tumors  were  able  finally  to  rid  themselves  of  their  growths. 

Histology  of  Receding  Tumors 

Bashford,  Murray,  and  Cramer  '"  examined  microscopically  a  re- 
ceding tumor  of  the  Jensen  strain  and  found  necrosis  and  a  great 
overgrowth  of  connective  tissue,  coupled  with  the  presence  of  char- 
acteristic cells  containing  small  nuclei  and  a  coarse  protoplasmic  re- 
ticulum, a  type  which  they  had  ^encountered  in  growths  exposed  to 
radium,  and  especially  about  those  of  animals  that  had  received  toxic 
doses  of  adrenahn.  In  some  areas  a  few  isolated  tumor  cells  were 
found  lying  in  a  dense  connective  tissue,  and  associated  with  multi- 
nucleated cell  masses  like  those  common  in  the  reaction  zone  around 
foreign  bodies.  As  even  an  extensive  necrosis  of  the  parenchyma  had 
never  of  itself  been  sufiicient  to  excite  such  an  active  connective  tissue 
proHferation  in  transplantable  tumors,  the  authors  were  incHned  to 
connect  this  fibrosis  with  the  occurrence  of  hemorrhages  in  the  tumor. 
Bashford,  Murray,  and  Bowen  ^  described  a  cell  with  darkly  staining 

^  Med.  News,  1905,  Ixxxvii,  968. 

^  Surgery,  Gynecology,  and  Obstetrics,  1906,  ii,  633. 

^  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  63. 

'^British  Med.  Jour.,  1906,  ii,  209. 

Lancet,  1906,  ii,  315. 
^  Sci.  Reports,  Imperial  Cancer  Research  Futid,  London,  1905,  No.  2,  Part  ii,  63. 
^  Proc.  Roy.  Soc,  Series  B,  1906,  Ixxviii,  212. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  302. 


92  THE    TRANSPLANTED    TUMOR 

nucleus  and  protoplasm  that  was  often  present  in  spontaneously  re- 
gressing tumors,  and  Bashford,  Murray,  and  Cramer/  the  occurrence 
of  energetic  phagocytosis. 

The  histological  data  recounted  and  pictured  by  Gaylord  and 
Clowes  -  consisted  of  retrogressive  changes  in  the  epithehum  accom- 
panied by  the  occasional  fusion  of  some  of  its  cells  to  form  pseudo- 
giant  cells,  the  appearance  of  hemorrhagic  areas,  an  ingrowth  of 
connective  tissue  spHtting  alveoli  into  smaller  cell  groups,  and  the 
accumulation  of  small  round  cells. 

CLINICAL   COURSE   OF   THE    TRANSPLANTED    TUMOR 

Bashford,  Murray,  and  Cramer,^  after  two  years'  observation  of  al- 
most three  thousand  mice  with  propagable  tumors,  concluded  that  the 
presence  of  such  a  growth,  even  when  it  was  of  greater  weight  than  the 
mouse  itself,  did  not  necessarily  involve  any  disturbance  of  the  normal 
nutrition  which  could  be  regarded  as  comparable  to  the  cachexia  fre- 
quently associated  with  mahgnant  new  growths  in  the  human  subject. 
The  animals  were  able  to  support  large  growths  for  several  months,  and 
even  massive  tumors  in  the  abdominal  ca\-ity  and  extensive  metas- 
tases in  the  lungs,  \vithout  visible  inconvenience.  But  when  abrasions 
occurred  in  the  skin  overlying  a  tumor,  the  hemorrhage  and  septic 
infection  which  followed  speedily  produced  marked  constitutional  ef- 
fects, among  which  emaciation  was  almost  constantly  present,  and 
the  mice  seldom  sur\dved  for  many  days.  Taken  as  a  whole,  the 
condition  of  animals  mth  ulcerated  tumors  closely  reproduced  that 
of  cachexia  in  man,  but  in  the  case  of  subcutaneous  tumors  which 
did  not  involve  any  important  organ,  cachexia  could  be  definitely 
assigned  to  a  position  of  secondary  importance  as  an  occasional  accom- 
paniment of  mahgnant  growths,  to  which  it  had  no  essential  relation 
whatsoever. 

Moreschi  '*  investigated  the  association  between  tumor  growth  and 
nourishment,  using  for  the  purpose  a  mouse  sarcoma  of  great  proHfera- 

1  Prcc.  Roy.  Soc,  Series  B,  1907,  Ixxix,  187. 
Third  Set.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  340. 
^  Surgery,  Gynecology,  and  Obstetrics,  1906,  ii,  633. 

'  Sci.  Reports,  Imperial  Cancer  Research  Fmid,  London,  1905,  No.  2,  Part  ii,  40. 
*  Zeitschrifi  f.  I mmunitdtsforsch.,  etc.,  Orig.,  1909,  ii,  651. 


THE    TRANSPLANTED    TUMOR 


93 


tive  energy.  He  found  that  a  moderate  restriction  of  the  amount  of 
food  was  followed  by  a  retardation  of  tumor  growth  and  a  lengthen- 
ing of  the  life  of  the  animals  as  compared  with  controls  fed  in  the 
usual  way,  while  an  extreme  condition  of  malnutrition  preceding  in- 
noculation  might  cause  a  great  decrease  in  growth,  or  even  prevent 
it  entirely.  The  death  of  a  tumor-bearing  animal  Moreschi  referred, 
not  to  a  lack  of  the  ordinary  food-stuffs,  but  to  withdrawal  by  the 
tumor  of  a  specific,  autogenous,  nutrient  material  essential  to  life. 

Following  up  these  experiments,  Rous  ^  inquired  whether  it  might 
not  be  possible  to  delay  the  course  of  inoperable  tumors,  or  to  hinder 
the  development. of  metastases  after  the  excision  of  a  primary  growth, 
by  restricting  the  diet.  In  an  attempt  to  answer  these  questions 
a  series  of  experiments  was  undertaken  with  the  Flexner-Jobling 
carcinoma  of  the  rat.  Contrary  to  expectation  it  was  found  that 
large  tumors  continued  to  grow  with  the  same  rapidity  in  hosts  emaci- 
ating on  an  insufficient  diet  as  in  controls  fed  on  a  full  one,  many  of 
which  were  gaining  weight.  With  still  larger  tumors,  in  hosts  already 
cachectic,  the  withholdin£_of  sufficient  food  had  as  little  effect  upon 
the  tumor  as  it  had  upon  the  frequenQ^_jof  metastasis  formation. 
Moreschi's  findings  were  thus  corroborated,  so  far  as  concerned  the  in- 
fluence of  limited  nourishment  upon  the  development  of  tumor  grafts. 
When  food  restriction  was  begun  four  days  after  the  introduction  of 
the  grafts  it  was  noted  that  the  tumors  developed  a  little  more  slowly 
than  in  the  controls. 

Medigreceanu  -  estimated  the  weights  of  various  organs  in  rats 
and  mice  bearing  transplantable  or  spontaneous  tumors.  The  ratio  of 
the  ahmentary  canal  to  the  body  weight  (less  that  of  the. tumor)  was 
within  the  normal  limits,  while  that  of  the  lungs  and  spleen  was  vari- 
able. The  relative  weights  of  the  kidneys  of  tumor-bearing  (and 
pregnant)  mice  showed  only  such  slight  variations  as  were  met  with  in 
normal  animals,  but  a  transplantable  rat  sarcoma,  on  the  contrary, 
induced  constantly  an  increase  in  the  size  of  these  organs  which  was 
directly  proportional  to  the  size  of  the  tumors.  However,  as  mouse 
sarcomata  did  not  reproduce  this  phenomenon  in  mice,  the  change 

^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1910-1911,  viii,  128 
^  Proc.  Roy.  Soc,  Series  B,  1909-1910,  Ixxxii,  286. 
Berl.  klin.  Woch.,  1910,  xlvii,  588. 


94  THE   TRANSPLANTED    TUMOR 

was  not  thought  to  be  characteristic  of  the  sarcomata.  The  heart 
was  enlarged  in  rats  and  mice  bearing  tumors,  generally  in  proportion 
to  the  weight_of  the^growth,  but  rapidly  proliferating  neoplasms  did  not 
lead  to  such  marked  hypertrophy  as  did  those  which  were  increasing 
more  slowly  and  were  richly  suppHed  with  blood.  Hypertrophy  of 
the  heart  in  tumor-bearing  animals  the  author  was  inclined  to  refer 
to  the  action  of  mechanical  factors.  The  pregnant  normal  animals 
examined  did  not  present  a  corresponding  cardiac  enlargement. 

The  important  result  of  the  experiment  was,  however,  the  demon- 
stration that  the  liver  was  hypertrophied  in  all  animals  bearing  either 
transplanted  or  spontaneous  tumors,  and  a  general  parallel  subsisted 
between  the  weight  of  the  tumor  and  the  weight  of  the  liver,  whether 
comparison  were  made  between  different  growths  of  the  same  strain, 
or  tumors  of  different  strains.  This  disturbance  of  the  normal  ratio 
was  due  neither  to  a  loss  of  weight  in  the  other  organs  nor  to  the  at- 
tainment by  the  liver  of  a  weight  equivalent  to  what  it  would  have 
reached  in  the  same  animal  during  the  natural  augmentation  of  the 
body  weight.  There  were,  moreover,  differences  between  the  Hxers  of 
normal  and  tumor  animals,  such  as  the  increased  percentage  of  water 
in  the  latter  (as  high  as  4  to  5%  more  than  in  normals),  which  in- 
dicated the  presence  of  quaHtative  differences  as  well.  Histological 
studies  had  not  indicated  any  anatomical  changes.  In  a  rat  in  which 
a  tumor  of  ten  to  twelve  grams  had  disappeared  by  spontaneous  ab- 
sorption, the  liver  was  still  enlarged  when  examined  twenty  days  after 
complete  recession  of  the  growth,  a  finding  which  the  author  contrasted 
with  the  fact  that  the  hypertrophy  of  the  Hver  found  in  pregnant  mice 
vanished  a  short  time  after  the  birth  of  the  young. 

As  a  corollary  to  these  experiments  Medigreceanu  ^  undertook  to 
determine  whether  augmentation  in  weight  were  due  to  an  increment 
in  the  diet.  The  simplest  explanation  of  the  circumstance  would  be 
that  the  growing  tumor  attracted  nourishment  to  itself  and  left  the 
host  in  a  condition  of  partial  starvation,  as  a  logical  consequence  of 
which  there  would  follow  an  increased  appetite  and  the  ingestion  of  a 
larger  amount  of  food  to  satisfy  the  demands  of  the  organism  and  its 
growing  tumor.  This  hypothesis,  if  it  were  justifiable,  would  account 
for  the  hypertrophy  of  the  Hver,  which  would  have  more  work  to  per- 

1  Berl.  kUn.  Woch.,  1910,  xlvii,  772. 


THE   TRANSPLANTED   TUMOR  95 

form.  Experiments  directed  toward  the  solution  of  this  question 
demonstrated  that  there  was  no  more  food  ingested  by  tumor-bearing 
rats  than  by  normal  ones,  that  the  body  weight  (less  tumor)  increased 
for  a  time  after  transplantation,  as  in  normal  controls,  and  then  began 
to  diminish,  and  that  during  this  period  of  loss  in  weight  the  appetite 
was  decreased.  The  hypertrophy  of  the  liver  'in  tumor  rats  could 
not,  therefore,  be  explained  by  an  increased  intake  of  food. 

Amyloid  degeneration  has  been  described  by  several  authors  in  the 
spleens  of  mice  bearing  transplanted  tumors.  Thus,  Albrecht  and 
Hecht,^  in  discussing  the  enlargement  of  the  spleen  so  commonly 
found  in  tumor  mice,  ascribed  it  to  bacterial  infection,  and  said  further 
that  amyloidosis  finally  made  its  appearance  in  these  organs. 

Lubarsch  ^  found  amyloid  degeneration  of  the  spleen,  liver,  kidney, 
adrenal,  and  pancreas,  in  the  order  of  frequency  named,  among  forty- 
two  mice  with  transplantable  tumors.  While  the  presence  of  amyloid 
was  not  dependent  upon  the  histology  of  the  growths,  occurring  as  it 
did  in  animals  bearing  sarcoma,  carcino-sarcoma,  and  carcinoma,  it  was 
of  more  frequent  occurrence  and  of  earlier  appearance  among  mice 
with  sarcoma  or  carcino-sarcoma  than  among  those  with  pure  car- 
cinoma. No  relation  could  be  demonstrated  between  amyloid  degen- 
eration and  the  size  of  the  turr^or.  Lubarsch  did  not  beheve  that  the 
presence  of  amyloid  could  always  be  referred  to  an  antecedent  bacterial 
infection,  and  suggested  its  possible  association  with  the  products  of 
the  necrosis  of  tumor  tissue. 

Freytag  ^  examined  forty  mice  with  non-ulcerated  tumors  in  which 
bacteria  were  not  microscopically  demonstrable.  In  most  of  the  cases 
the  spleeiL.was_erilarged,  and  in  thirty-three  it  was  the  seat  of  amyloid 
degeneration.  The  livers  in  twenty-six  showed  the  same  lesion,  and  the 
kidneys  a  trace  of  it  in  eleven.  Among  sixteen  mice  which  had  been 
inoculated  unsuccessfully,  amyloid  degeneration  could  be  demonstrated 
in  the  spleen  in  nine  and  in  the  Kver  in  five,  but  in  only  two  was 
it  present  in  the  kidneys,  and  in  both  of  these  the  amount  was  very 
limited.  It  thus  appeared  that  tne  cell  destruction  resulting  from 
one  or  two  fruitless  inoculations  might  inaugurate  an  amyloid  degenera- 

1  Centralbl.  f.  allg.  Path.,  etc.,  1909,  xx,  1039. 
^  Ceniralbl.  f.  allg.  Path.,  etc.,  1910,  xxi,  97. 
'^  Zeitschrift  f.  Krebsforsch.,  1910-1911,  x,  164. 


96  THE    TRANSPLANTED   TUMOR 

tion,  although  it  was  possible  that  in  an  animal  like  the  white  mouse 
which,  as  Davidsohn  ^  had  already  shown,  was  very  prone  to  amyloid 
degeneration  of  its  organs,  this  lesion  might  occur  spontaneously  with 
relative,  frequency.  Twenty  normal  mice  were,  therefore,  examined, 
but  without  anything  of  moment  being  found  in  either  spleen  or  kidney; 
although  the  Hver  often  showed  a  sHght  degree  of  fatty  degeneration,  the 
amyloid  reaction  was  always  negative.  Still,  these  mice  were  all  very 
young,  and  experiments  were  in  contemplation  which  should  deal  with 
normal  animals  that  had  been  kept  as  long  in  confinement  as  the  tumor 
mice,  and  upon  a  similar  diet. 

Price- Jones '  studied  the  blood  of  sixteen  mice  with  transplantable 
carcinoma,  and  found  a  slight  degree  of  anemia,  indicated  by  a  lowered 
hemoglobin  content  and  a  diminution  of  the  number  of  red  blood  cells 
per  cubic  millimeter.  A  well-marked  leucocytosis  was  present,  due 
to  a  great  relative  and  absolute  increase  in  the  large  mononuclear 
lymphoid  cells  and  the  polymorphonuclear  leucocytes.  Little  change 
could  be  found  in  the  marrow  of  these  mice  for,  owing  to  the  aug- 
mented myeloid  activity  of  their  spleens,  any  increased  vigor  on  the 
part  of  the  marrow  was  either  masked  or  obviated.  Thirteen  normal 
mice  served  as  controls. 

A  diniinutiorLin^oxygencapacity  with  a  fall  in  the  percentage  of 
hemoglobin  parallel  to  the  decrease^  in  nuniber  of  red  cells  per  cubic 
millimeter,  was  found  by  Chishohn  ^  in  the  blood  of  rats^Jbearing 
tranjpJanted_sgxcQmata.  The  anemia,  which  was  usually  accom- 
panied by  a  wasting  of  the  body  tissues,  did  not  depend  on  the  presence 
of  ulceration  nor  was  it  in  all  cases  proportional  to  the  amount  of 
necrosis  in  the  tumor.  Signs  of  regeneration  present  in  the  blood 
smears  indicated  that  the  anemia  was  due,  at  least  in  part,  to  blood 
destruction,  but  the  mechanism  of  its  production  was  uncertain.  The 
presence  of  the  tumor  was  associated  with  an  increase  in  the  total  vol- 
ume of  the  blood.  In  certain  exceptional  cases  there  was  reason  to 
beHeve  that  the  animal  increased  both  its  oxygen  capacity  and  blood 
volume  to  meet  the  needs  of  the  tumor,  but  this  occurred  only  in  the 
case  of  small  growths. 

'  Verhandl.  d.  deiitschen  path.  GcseUsch.,  1904,  yte  Tagung,  41. 
2  Arch.  Middlesex  Hosp.,  1911,  xxiii,  56. 
^  Jour.  Path,  and  Bad.,  1911,  xvi,  152. 


THE    TRANSPLANTED   TUMOR 


97 


In  a  review,  Cramer  ^  said  that  he  had  discovered  no  diminution 
in  the  total  acidity  of  the  gastric  contents  in  mice  that  had  been  suc- 
cessfully inoculated  with  the  Jensen  tumor. 

Copeman  and  Hake-  found  an  increase  of  the  physiologically  active 
hydrochloric  acid  (including  both  free  acid  and  that  combined  with 
proteids  and  nitrogenous  organic  bases)  in  the  gastric  contents  of 
mice  and  rats  bearing  transpLlanted._tumors,  and  in  mice  with  spon- 
taneous growths.  The  stomachs  of  one  hundred  and  fifty  normal  mice, 
where  no  account  was  taken  of  the  period  of  digestion,  gave  an  average 
of  O.I  1 21%  hydrochloric  acid,  while  in  one  hundred  and  seventy-eight 
mice  with  transplanted  tumors  the  average  was  0.1752  %.  An  average 
of  two  hundred  and  forty-five  stomachs  from  normal  mice  for  periods 
of  digestion  varying  from  one  to  one  and  one-half  hours  gave  0.1456% 
hydrochloric  acid,  and  of  two  hundred  and  ninety  stomachs  from  mice 
with  transplanted  tumors,  0.1673%.  Fifteen  stomachs  of  mice  which 
were  the  subjects  of  spontaneous  neoplasms  showed  an  average  of 
0.1929%  hydrochloric  acid  during  different  uncertain  periods  of  diges- 
tion. An  average  of  the  stomachs  of  six  normal  rats  after  one  hour's 
digestion  gave  0.1427%  hydrochloric  acid,  and  of  seven  rats  with 
transplanted  growths  (varying  from  0.3  to  15  grams)  0.1837%  after 
the  same  period. 

Regarding  experiments  on  animals  bearing  transplanted  tumors 
Cramer  ^  indicated  the  importance  of  recognizing  the  difference  be- 
tween an  animal  with  a  propagable  tumor  and  one  the  subject  of  a 
spontaneous  growth,  pointing  out  that  the  question  whether  the  in- 
crease in  hydrochloric  acid  in  animals  bearing  transplanted  tumors 
was  connected  in  any  way  with  the  decrease  of  this  substance  observed 
clinically  in   man  should  still  be  considered,  therefore,  an  open  one. 

The  same  author,^  as  the  result  of  an  inquiry  into  the  gaseous  metab- 
olism of  rats  bearing  the  Jensen  rat  sarcoma,  found  that  the  growth 
of  a  tumor  in  a  normal  organism  led  at  first  to  physiological  changes 
only,  tumor  growth  causing  a  distinct  increase  in  the  weights  of  the 

'  Biochem.  Centralbl.,  1905,  iv,  65. 

-  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,   1908,  398. 

Proc.  Roy.  Soc,  Series  B,  1908,  Ixxx,  444. 
^  Metabolism  and  Practical  Medicine,  v.  Noorden,  London,  1907,  vol.  iii,  824. 
^  Third  Sci.  Report,  Lmperial  Cancer  Research  Fund,  London,  1908,  427. 


gS  THE    TRANSPLANTED    TUMOR 

animals,  and  that  pathological  changes  in  the  general  metabolism  did 
not  ensue  until  the  physiological  resources  had  become  exhausted.  He 
compared  the  effect  exerted  on  the  body  by  a  growing  tumor,  in  so  far 
as  it  was  a  problem  of  nutrition,  to  that  of  the  growth  of  a  fetus  in  a 
pregnant  animal.  It  could  not  be  explained  by  attributing  to  the 
cancer  cell  the  formation  of  pathogenic  substances  of  a  h}^othetical 
nature,  such  as  a  "cancer  ferment"  or  a  "cancer  toxin." 

Cramer's  findings  in  the  case  of  rats  bearing  tumors,  and  his  com- 
parison of  such  rats  to  pregnant  animals,  form  an  interesting  supple- 
ment to  some  experiments  conducted  many  years  ago  by  Edelfsen 
and  Hensen.^  These  authors  demonstrated  that  female  guinea-pigs 
grew  at  about  the  same  rate  whether  they  had  young  or  not  during 
their  own  period  of  growth.  Minot  ^  was  able  fully  to  confirm  these 
statements,  and  concluded  from  his  own  experiments  that  gestation 
did  not  represent  a  tax  on  the  mother,  but  a  stimulus  —  that  it  favored, 
rather  than_impeded,  growth. 

Cramer  and  Pringle  ^  determined  the  nitrogenous  metabolism  in 
three  rats  before  and  after  the  implantation  of  the  Jensen  rat  sarcoma. 
Their  conclusions  were  appKed  only  to  animals  bearing  tumors  of 
sufficient  size  to  warrant  the  assumption  that  they  would  reveal  any 
specific  property  or  function  which  might  be  possessed  by  the  cells  of 
a  neoplasm.  The  eft'ects  which  a  large  tumor  must  necessarily  pro- 
duce, by  \drtue  of  its  mere  mass,  were  not  considered.  The  main  out- 
come of  the  experiments  was  stated  in  the  following  conclusions :  — 

"  I.  Less  nitrogen  is  necessary  to  build  up  a  certain  weight  of  tumour 
tissue  than  is  necessary  to  build  up  an  equal  weight  of  the  somatic 
tissues  of  the  host. 

"2.  Animals  bearing  tumours  maintain  their  positive  nitrogen  bal- 
ance, and  the  nitrogen  retention  actually  increases  with  the  size  of  the 
tumour. 

"3.  In  our  experiments  the  cells  of  the  new  growth  derived  their 
nitrogenous  material  necessary  for  the  building  up  of  new  tissue  by 
a  sparing  action  on  the  protein  metaboHsm.  The  tumour  cells  do  not 
proliferate  at  the  expense  of  the  tissues  of  the  host,  nor  is  there  any 

1  Arb.  a.  d.  Kieler  Physiol.  Inst.,  1868.     Cited  by  Minot. 

^  Jour.  Physiol.,  1891,  xii,  141. 

^  Proc.  Roy.  Soc,  Series  B,  1909-1910,  Lxxxii,  307. 


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J.  R.  FoTd,  del. 

Mammary  chondro-osteo-sarcoma  of  mouse.     Primary  tumor.    Spindle-cell  sarcoma;  at  left  of  figure 
an  acinus  lined  by  columnar  cells  —  mouse  nearing  end  of  pregnancy.     X  -j-. 


WI^^^^S^ 


J  1     I    rd  a  I 

Transplanted  tumor  from  first  generation  of  growth  pictured  above.     Illustrates  also  the  structure  of  the 
recurrent  spontaneous  tumor,  which  contained  osteoid  nodules,  spindle  cells,  and  cartilage. 


THE    TRANSPLANTED    TUMOR  99 

e\ddence  that  they  have  a  higher  affinity  for  nutritive  material  than 
the  growing  cells  of  the  host. 

"4.  There  is  no  evidence  of  the  existence  of  substances  secreted  by 
the  tumour  disturbing  the  nitrogenous  metabolism  by  means  of  a  toxic 
action  on  the  tissues  of  the  host." 

If  now,  said  the  authors/  it  were  true  that  less  nitrogen  was  needed 
to  build  up  a  given  weight  of  tumor  tissue  than  was  necessary  to 
build  up  an  equal  weight  of  the  somatic  tissues  of  the  host,  it  would 
follow  that  cancer  would  have  a  lower  nitrogen  percentage  than  the 
somatic  tissues.  The  estimation  of  the  total  amount  of  nitrogen  (pro- 
tein and  non-coagulable  nitrogen)  in  various  tissues  of  the  three  rats 
mentioned  in  the  previous  article  was,  therefore,  undertaken,  and  the 
authors  were  able  to  show  that,  weight  for  weight,  the  malignant  cells 
contained  only  about  three-fourths  of  the  protein  nitrogen  present  in 
the  tissues  of  the  host.  In  other  words,  with  the  same  amount  of  pro- 
tein a  larger  mass  of  tumor  than  of  host  tissue  could  be  evolved.  In 
a  former  paper  Cramer  had  indicated  the  similarity  which  existed 
between  the  growth  of  cancer  and  the  growth  of  the  fetus,  and  prelim- 
inary experiments  by  Dr.  Lochhead  had  shown  that  a  rapidly  growing 
normal  tissue  (the  fetus)  had  a  lower  nitrogen  value  than  the  maternal 
organism.  i 

HISTOLOGICAL   VARIATIONS    OCCURRING   DURING   TRANSPLANTATION 

In  the  Parenchyma 

Distinct  variations  from  the  tunior_type  originally  transplanted  may 
occur  under  extended  propagation,  and  it  is  po^sible_for^these  to  be 
so  marked  that,  as  pointed  out  by  Bashford,  Murray,  and  Cramer,^ 
if  growths  with  the  characters  of  various  transplanted  tumors  in  the 
same  series  had  occurred  sporadically  they  might  well  be  regarded  by 
pathologists  as  totaUy_distinct  conditions.  Thus  an  acinous  arrange- 
ment of  the  parenchyma  was  a  nearly  constant  feature  of  tumors  ex- 
amined within  the  first  week  after  transplantation,  while  another 
characteristic  was  the  loose  columnar  arrangement  of  tumor  cells  in 
large  alveoH.     At  a  subsequent  stage  the  central  parts  of  certain  al- 

1  Proc.  Roy.  Soc,  Series  B,  1909-1910,  Ixxxii,  315. 

"  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  52. 


lOO  THE    TR.A.XSPLAXTED    TUMOR 

veoli  underwent  a  necrotic  change  and,  indeed,  in  advanced  states  of 
this  process  the  alveoH  might  consist  only  of  a  thin  layer  of  healthy 
cells  and  completely  necrotic  granular  central  areas.  On  the  other 
hand,  equally  large  alveoh  occurred  which  were  completely  filled  by 
healthy  cells  shoTsdng  no  traces  of  necrosis.  All  the  conditions  just 
discussed  might  be  discovered  in  different  areas  of  the  same  groAvth. 
The  authors  had  been  able  to  determine  that  these  different  histological 
appearances  were  not  demonstrable  at  uniform  fixed  periods  after  the 
date  of  inoculation,  whence  they  concluded  that  the  time  of  their  pro- 
duction was  not  determined  by  the  disturbance  of  nutrition  following 
transfer  from  one  host  to  another. 

^vlurray  ^  encountered  a  tumor  which  he  at  first  regarded  as  a  spindle 
cell  sarcoma,  recurrences  of  which  contained  hyaline  cartilage  and  un- 
calcified  bone.  Daughter  tumors  propagated  from  recurrences  showed 
the  same  great  variabihty  of  structure,  some  consisting  of  spindle  cells, 
others  showing  large  masses  of  cartilage  either  associated  with  osteoid 
tissue  or  alone,  while  in  one  instance  there  had  been  a  deposition  of  hme 
salts  in  the  osteoid  matrix,  so  that  true  bone  had  actually  been 
formed.  The  subsequent  history  of  this  tumor  as  given  by  Bashford^ 
Avas  that,  after  the  fourth  generation,  cartilage  and  osteoid 
tissue  disappeared  and  two  strains  with  divergent  characters  were 
obtained,  in  one  of  which  the  growths  were  soft,  consisting  of  closely 
packed  spindle  cells  Avith  \'ery  little  interstitial  collagenous  tissue  and 
large  necrotic  areas.  The  second,  deriA'ed  from  a  sclerotic  tumor  of 
the  eighth  generation,  dift'ered  in  seA^eral  particulars.  Its  tumors  Avere 
firm,  strongly  collagenous,  Avith  httle  or  no  necrosis  even  AA'hen  they 
had  reached  a  large  size,  and  these  dift'erences  had  been  maintained,  at 
the  time  of  AArriting,  for  over  tAvo  years. 

^Murray  ^  reported,  further,  a  mammary  tumor  of  the  mouse  contain- 
ing three  distinct  histological  structures  —  keratinized  alveoH,  solid 
ah-eoK,  and  adenomatous  areas.  In  the  first  feAv  generations  of  trans- 
planted tumors  the  groAvths  generally  presented  a  sohd  structure 
Avith  only  minute  areas  of  keratinization,  a  condition  AA'hich  continued 
Avith  a  sHght  progressive  increase  in  the    amount    of    keratin   until 

^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  78. 
'^Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1911,  178. 
^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  159. 


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Osteo-chondro-sarcoma  of  the  mouse.     38-day-old  tumor  from  36th  generation  of  a  soft,  necrotic  strain 
in  which  very  little  collagen  is  produced.     X  V- 


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36-day-old  growth,  31st  generation  of  a  sister  strain  of  above.     The  tumors  of  this  series  are  firm,  and 
produce  an  abundant  amount  of  collagen.     X  \^ 


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THE    TRANSPLANTED    TUMOR  lOI 

the  sLxth  generation.  In  the  seventh,  however,  keratinization  ap- 
peared to  an  even  more  pronounced  degree  than  in  the  primary 
tumor  and  endured  for  three  or  four  generations,  after  which  it  dimin- 
ished. At  the  conclusion  of  this  period  the  tumors  consisted  of 
large  alveoH  of  closely  packed,  small  cells,  interrupted  only  by  an 
occasional  capillary.  Upon  this  medullary  condition  of  the  paren- 
chyma, and  after  it  had  persisted  through  several  generations,  there 
intruded  a  well-marked  adenomatous  structure,  which  involved  some 
tumors  to  such  an  extent  that  considerable  portions  of  them  pre- 
sented the  appearance  of  an  adenoma.  Others  exhibited  the  formation 
of  adeno-carcinoma,  while  still  others  had  preserved  their  alveolar 
arrangement.  Murray  pointed  out  that  separation  of  the  keratinized 
and  adenomatous  t}'pes  by  a  long  interval  of  time,  during  which  there 
had  been  many  successive  transferences  from  animal  to  animal, 
proved  that  the  two  differentiations,  however  distinct  they  might 
appear,  were  inherent  in  cells  of  one  kind.  It  was  of  merely  academic 
interest  to  argue  whether  the  original  growth  should  be  considered  a 
squamous  cell  carcinoma  capable  of  grovvdng  as  an  adeno-carcinoma, 
or,  conversely,  an  adeno-carcinoma  of  the  mamma  in  which  excessive 
keratinization  had  occurred.  Bashford  ^  has  described  the  subsequent 
history  of  this  strain,  which  at  the  time  of  writing  had  been  propagated 
through  eighty- two  generations.  The  acinous  structure  disappeared 
after  the  t^/^lfth  generation  and  since  then  the  tumor  had  been  culti- 
vate(l  as  a  pure  alveolar  carcinoma  without  any  differentiation  whatso- 
ev-er,  except  in  one  very  old  tumor  (eight  months)  of  the  fifty-sixth 
generation,  which  showed  areas  of  keratinization. 

A  mo^t  comprehensive  review  of  the  behavior  of  the  tumor  cell 
during  extended^propagation  has  been  written  by  Bashford,^  based 
upon  observation  of  spontaneous  tumors  in  over  six  hundred  and_fifty 
mice,  as  well  as  eighty-five  propagable  tumors,  thirty-five  of  which 
had  been  in  cultivation  for  more  than  three  years. 

Generally  speaking,  the  results  following  the  continuous  propagation 
of  an  extremely  varied  series  of  tumors  showed  a  remarkable  average 
constancy  over  long  periods  among  both  the  carcinomata  and  sar- 
comata.    The    morphological    variations    which    had    been    observed 

^  Fourth  Set.  Report,  Imperial  Cancer  Research  Fund,  London,  1911,  155. 
.  "^Fourth  Sei.  Report,  Imperial  Cancer  Research  Fund,  London,  1911,  131. 


I02  THE    TR.\NSPLAXTED    TUMOR 

were  but  slight  and,  T\dth  few  exceptions,  served  only  to  emphasize 
this  statement.  The  apparent  loss  of  acinous  structure  in  the  later 
generations  of  many  adeno-carcinomata  of  the  mamma  was  hardly  to 
be  considered  as  exddence  of  a  real  change.  In  some  tumors,  examina- 
tion at  a  short  interval  after  transplantation  revealed  a  purely  alveolar 
condition,  which  gradually  gave  wa}^  to  a  t>^ical  acinous  structure 
as  the  tumors  grew  older,  and  which  might  even  be  entirely  replaced 
by  perfect  acini  in  very  old  tumors.  This  fact  showed  the  necessity 
for  examination  of  old  tumors  in  all  cases  where  normal  histological 
differentiations  present  in  the  primary  growth  or  in  the  earlier  gen- 
erations of  daughter  tumors  were  absent  in  young  tumors  of  later 
generations  used  for  transplantation.  WTien  this  precaution  was 
observed,  adeno-carcinomata  primarily  hemorrhagic  might  be  found 
to  reproduce  their  original  hemorrhagic  character,  even  though  it 
had  been  absent  in  the  periods  immediately  succeeding  transplantation. 
The  same  statement  could  be  applied,  also,  to  certain  of  the  squamous 
cell  carcinomata.  The  differences  in  histological  structure  between 
the  spontaneous  tumor  and  its  early  daughter  tumors  on  the  one  hand, 
and  the  later  transplanted  growths  on  the  other  were,  therefore,  not 
necessarily  final  e^-idence  of  a  real  change  in  the  character  of  the 
parenchyma  in  ever}'  case  in  which  they  were  found. 

As  already  stated,  the  general  conclusion  was  drawn  that  the  cells  of 
many  tumor  parenchymata  preserved  unaltered  and  in  the  most  per- 
sistent manner  the  majority  of  the  characters  with  which  they  were 
endowed  from  the  earhest  period  at  which  they  had  come  imder  obser- 
vation. The  various  strains  did  not  approximate  a  common  type  either 
in  structure,  rate  of  growth,  or  inoculation  percentage ;  and  while  a 
number  of  strains  might  be  selected  as  forming  a  group  homogeneous 
in  naked  eye  structure  and  in  histology,  it  could  be  demonstrated  that 
the  similarity  was  primary  and  already  associated  with  the  sponta- 
neous tumors,  rather  than  a  secondary  convergence  from  an  initial 
heterogeneous  condition.  The  conclusion  seemed  warranted  that  the 
relative  permanence  of  the  distinctive  characteristics  in  typical  tumor 
strains  had  its  foundation  in  the  cellular  changes  by  which  the  non- 
cancerous tissue  cells  had  passed  over  into  the  cancerous  state,  and 
this  persistence  suggested  how  radical  must  have  been  the  alterations 
of  which  cancerous  transformation  was  the  expression. 


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THE   TRANSPLANTED    TUMOR  IO3 

Bashford  arranged  his  tumors  in  groups  according  to  whether  they 
showed  only  minor  alterations  from  the  primary  growth,  definite  tem- 
porary, or  permanent,  alterations.  In  the  first  there  were  fourteen 
mammary  adeno-carcinomata,  five  of  which  were  hemorrhagic  and 
four  papilhferous,  two  sarcomata,  a  sebaceous  adeno-carcinoma  of  the 
axilla,  two  carcinomata  of  the  preputial  gland,  and  a  strongly  keratiniz- 
ing squamous  cell  carcinoma  of  the  orbital  region.  The  second  class 
differed  but  slightly  from  the  first  in  that  certain  definite  changes 
in  structure  or  behavior  appeared,  persisted  for  a  time,  and  then 
vanished.  Its  members  were  all  mammary  carcinomata,  and  the  main 
variations  affected  the  relative  amounts  of  alveolar  or  acinous  structure 
or,  as  in  a  few  cases,  were  concerned  with  the  appearance  in  the  stroma 
of  spindle  shaped  cells  undoubtedly  of  parenchymatous  origin,  al- 
though they  were  strikingly  hke  those  of  a  sarcoma. 

Placed  in  the  third  group  were  those  tumors  among  which  changes 
in  structure  or  behavior  had  been  maintained.  This  division  comprised 
seventeen  mammary  carcinomata,  two  adeno-cancroids,  a  sebaceous  car- 
cinoma, a  squamous  cell  carcinoma,  an  osteo-chondro-sarcoma,  and  an 
osteo-sarcoma,  and  the  mutations  which  had  occurred  in  them  were 
mainly  the  assumption  of  a  more  alveolar  type,  the  disappearance  of 
keratin,  or  of  both  sebaceous  differentiation  and  keratin,  a  diminution 
in  the  amount  of  sebaceous  differentiation  with  increased  keratiniza- 
tion,  and  the  disappearance  of  epithehal  cells  growing  out  diffusely 
into  the  stroma. 

His  experience  of  spontaneous  and  transplanted  tumors  enabled 
Bashford  to  approach  certain  theoretical  aspects  of  oncology,  among 
them  V.  Hansemann's  assertion  that  metastases  in  the  human  subject 
were  less  differentiated  than  the  primary  growth  because  they  were 
more  anaplastic.  They  were  often  undifferentiated,  it  was  true,  but 
merely  because  they  had  not  had  time  in  which  to  dift'erentiate. 
The  doctrine  of  anaplasia  as  a  progressive,  irreversible  change  in 
cancer  cells  had  accordingly  lost  its  objective  basis,  and  had  become 
a  matter  of  subsidiary  importance. 

The  artificial  propagation  of  a  number  of  tumors  over  considerable 
periods  of  time  had  given  an  answer  to  a  conundrum  in  the  domain 
of  metaplasia  that  had  hitherto  been  insoluble  :  Of  what  differentiation 
would  metaplastic  cells  be  capable  if  they  continued  to  proHferate  ? 


I04  THE   TRANSPLANTED   TUMOR 

The  evidence  was  quite  clear  that  the  occurrence  of  one  differentiation 
did  not  preclude  the  later  development  of  another,  for  the  parenchy- 
mata  of  such  tumors  as  adeno-cancroids,  osteo-chondro-sarcomata, 
and  adeno-carcinomata  with  spindle  shaped  epithelium  were  capable 
of  either  differentiation  over  long  intervals,  and  presented  one  or  the 
other  for  reasons  independent  of  the  conditions  of  growth.  It  was 
probably  wrong  to  regard  as  evidence  of  lost  differentiation  periods 
during  which  this  faculty  was  absent,  and  they  might  be  interpreted 
more  properly  as  latent  periods.  No  other  assumption  was  compati- 
ble with  the  reappearance  of  differentiation  in  spite  of  the  re- 
peated subdivisions  to  which  a  tumor  parenchyma  had  been  subjected 
during  propagation  throughout  long  periods  of  time,  for  after  a  few 
transfers  all  the  cells  of  a  growth  in  any  one  animal  would  be  the 
descendants  of  a  single  cell  in  a  preceding  generation  not  very  remote. 
The  restoration  of  two  distinct  differentiations  in  later  generations  in 
the  same  form  and  association  in  which  they  had  been  encountered 
in  the  primary  tumor  could  accord  only,  therefore,  with  the  assump- 
tion of  a  homogeneous  parenchyma  possessed  of  dual  powers  .of  differ- 
entiation. 

Bashford's  paper  contained,  furthermore,  certain  important  sugges- 
tions on  the  relations  existing  between  structure  and  mahgnancy.  While 
most  of  the  transplantable  strains  had  shown  marked  deviations  from 
the  normal  structure  of  the  tissue  which  had  given  them  origin,  it  was 
not  an  invariable  rule  for  such  mutations  to  progress  further  during 
continued  propagation.  Hence  complete  loss,  or  even  latency  of 
differentiation,  was  not  at  all  necessary  for  unlimited  growth  and, 
indeed,  the  purely  glandular  structure  of  several  adeno-carcinomata 
of  the  mamma  afforded  evidence  that  the  capabihty  for  proliferation 
was  not  necessarily  dependent  upon,  or  accompanied  by,  marked 
changes  of  structure.  Other  tumors  also,  with  a  high  or  almost  com- 
plete degree  of  differentiation,  showed  this  capability  for  propaga- 
tion, among  these  being  squamous  cell  carcinomata  and  adenomata 
of  the  sebaceous  and  preputial  glands  which,  having  retained  their 
characteristic  differentiations  and  secretory  functions,  reminded  one 
strongly  of  a  type  of  malignant  growth  of  the  thyroid  in  man  and 
animals.  It  had  thus  been  demonstrated  that  tumors  distrnguishable 
under^the  microscope  only  with  difficultv  from  their  normaLiH2^^^^ 


iV^ 


J.  R.  Ford,  del. 

ideno- carcinoma  of  the  preputial  gland,  male 
mouse,  showing  its  close  resemblance  to  the 
normal  gland  in  spite  of  its  definitely  malig- 
nant character.  The  propagated  tumors  retain 
the  same  histological  picture.     X  ^.  ' 


J.  R.  FoTd,  del. 
Normal  preputial  gland  from  adult  male  mouse,  for  com- 
parison with  tumor  in  left-hand  illustration.     The 
larger  ducts  of  the  gland  are  lined  with  cells  resem- 
bling squamous  epithelium.     X  ^'r^. 


J.  R  Ford,  del. 
Sebaceous  adeno-carcinoma.     Spontaneous  tumor  in  left  groin,  showing  the  same  typical  differentiation 
as  the  cells  of  a  sebaceous  gland.     For  comparison  with  the  upper  left-hand  figure.     X  ^f-. 


THE    TRANSPLANTED    TUMOR  I05 

tissues,  were  capable  of  unlimited  propagation  —  a  fact  of  the 
highest  theoretical  importance  in  showing  the  independence  of 
biological  behavior  (malignancy)  and  structure.  So  far  as  the  reten- 
tion of  normal  histological  build  was  a  criterion  of  innocence,  its 
significance  had  been  lost,  and  at  the  time  of  writing  only  the  biologi- 
cal properties  of  some  tumors,  that  is,  their  power  of  unlimited  growth, 
distinguished  them  from  the  corresponding  normal  tissues. 

Apolant  ^  believed  that  characteristics  which  were  not  present  in  the 
spontaneous  tumor  could  never  arise  during  transplantation,  but  that 
altered  biological  conditions  surrounding  the  transplanted  growth 
allowed  certain  properties  to  appear  with  more  clearness  than  they 
had  in  the  primary  tumor.  Such  changes  proceeded  hand  in  hand 
with  increased  proliferative  power.  While  in  general  the  propagable 
neoplasms  thus  remained  true  to  the  type  of  the  spontaneous  growth 
from  which  they  had  been  derived,  certain  variations  might,  never- 
theless, occur  from  time  to  time. 

It  was  among  the  alveolar,  those  most  rapidly  growing  of  all  the  trans- 
plantable carcinomata,  that  the  characteristics  of  propagable  tumors 
appeared  in  their  most  salient  form.  Here  necrosis  supervened  in  the 
centers  of  the  alveoli  and  spread  progressively  with  the  increase  of 
the  tumor,  because  nutrition  was  unable  to  keep  pace  with  growth, 
the  maHgnant  tissue  meanwhile  continuing  its  proliferation  in  the  form 
of  a  relatively  narrow  surrounding  band.  Even  when  the  proliferative 
energy  was  intermediate,  the  alveolar  type  was  retained ;  but  coin- 
cident with  a  decrease  in  growth  power  isolated  cell  nests  emerged, 
the  stroma  became  more  vigorously  developed,  and  the  degeneration 
receded  very  perceptibly.  While  this  process  might  even  go  so  far  as 
to  produce  occasionally  an  acinous  structure,  such  a  condition  never 
progressed  to  any  considerable  degree. 

Appearance  and  disappearance  of  cysts  had  also  been  observed 
among  the  transplantable  alveolar  carcinomata,  but  to  a  very  variable 
extent.  In  some  strains,  cysts  were  almost  never  encountered,  while 
in  others  they  might  be  surprisingly  numerous. 

The  histological  expression  of  augmented  growth  energy  among  the 
fissure-forming  carcinomata  was  a  tendency  on  the  part  of  the  epithe- 

1  Arb.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  41. 
Verhandl.  d.  deiitschen  path.  Gesellsch.,  1908,  12*"  Tagung,  7. 


Io6  THE    TEANSPLANTED   TUMOR 

Hum.  more  marked  than  in  the  primary  tumors,  to  arrange  itself  in 
several  layers.  But  the  characteristic  property  of  this  type  of  carci- 
noma, the  formation  of  pleomorphous,  although  usually  fissure-hke 
lumina,  never  disappeared  entirely. 

Papillary  carcinomata  also  preserved  their  type  during  transplanta- 
tion, but  to  be  convinced  of  this  fact,  it  was  necessary  to  examine 
older  tumors,  because  growth  was  so  extraordinarily  slow  that  the 
process  required  a  long  time  for  its  completion.  In  the  first  one  or  two 
months  there  was  produced  only  the  alveolar  pre-stage,  marked  by  the 
presence  of  small  cell  nests,  most  of  which  contained  distinct  lumina. 
With  the  enlargement  of  these  lumina,  cell  processes  began  to  be  in- 
truded from  the  walls,  and  thus  in  the  course  of  many  weeks  or  months 
a  typical  papillary  carcinoma  was  evolved. 

Apolant^  had  under  observation  a  fissure-forming  carcinoma  which 
gradually  developed  into  a  growth  of  the  solid  type  with  a  scanty 
stroma,  while  later  still,  connective  tissue  no  longer  sharply  separated 
the  single  alveoli.  The  cells  toward  the  periphery  of  the  alveoli 
gradually  assumed  a  spindle  shape,  which  could  not  be  accounted 
for  by  the  effects  of  mechanical  pressure.  A  further  pecuHarity  of 
this  strain  was  an  isolation  of  the  cells  —  a  resolution  of  the  tumors 
into  their  elements,  which  made  it  hardly  justifiable,  from  a  purely 
histological  standpoint,  to  describe  the  growths  as  carcinomata. 
Apolant  was  not  certain  of  the  nature  of  the  change,  and  was  in  doubt 
whether  it  would  be  permissible  to  explain  the  alteration  as  the  begin- 
ning of  a  sarcomatous  transformation  solely  on  the  basis  of  this  his- 
tological picture.  Against  such  an  explanation  was  arrayed  the  ob- 
servation that  developing  sarcoma  was  always  separated  by  a  sharp 
boundary  from  the  carcinoma,  while  in  the  present  tumor  the  tran- 
sition was  gradual.  It  was,  therefore,  very  probable  that  the  spindle 
shaped  structures  were  merely  carcinoma  cells  which  had  undergone 
a  morphological  change. 

That  this  opinion  was  justified  was  shown  by  a  subsequent  article, 
in  which  Apolant^  wrote  that  at  the  one  hundred  and  thirty-ninth 
generation  of  the  tumor  all  the  spindle  elements  had  disappeared  and 
the  growth  had  reverted  to  a  typical  adeno-carcinoma. 

1  Verhandl.  d.  deiitschen  path.  Gesellsch.,  1908,  i2te  Tagung,  11. 
^Arch.f.  mikroskop.  Anat.,  1911,  Ixxviii,  144. 


THE    TRANSPLANTED    TUMOR  I07 

During  the  propagation  of  a  mammary  adeno-carcinoma  of  the  rat, 
first  described  by  Michaelis  and  Lewin/  Lewin  ^  observed  the  appear- 
ance of  an  alveolar  structure  in  the  second  and  third  generations,  with 
the  gradual  transformation  of  the  growth  into  one  of  soHd  type, 
and  almost  complete  regression  of  the  stroma.  In  the  third  gener- 
ation keratin  was  found.  In  some  tumors  of  the  fourth,  there  was 
a  considerable  increase  in  the  amount  of  stroma,  while  others  had 
a  scirrhous  appearance.  One  substrain  grew  as  a  pure  adeno- 
carcinoma, and  in  the  other  there  were  transitions  between  adeno- 
carcinoma and  cancroid.  In  the  fifth  generation  there  appeared  a 
pure  cancroid  with  no  admixture  of  glandular  elements,  and  in  the 
sixth,  a  pure  adeno-carcinoma,  a  solid  carcinoma  with  mucous  de- 
generation, and  a  pure  cancroid.  At  the  time  of  writing  the  growth  had 
reached  its  twelfth  passage,  in  which  no  tumor  of  a  pure  type  had  oc- 
curred but,  on  the  contrary,  mixtures  of  keratinized  adeno-carcinoma 
and  solid  carcinoma,  which  could  not  be  separated. 

Apolant^  was  convinced  that  the  histological  structure  of  trans- 
planted tumors  depended  upon  certain  conditions  in  the  host,  for 
in  a  strain  which  through  more  than  fifty  generations  had  been 
propagated  as  a  solid  reticular  carcinoma  he  encountered  a  distinctly 
adenomatous  build.  This  transformation,  however,  was  discoverable 
only  in  animals  that  had  been  partially  inimunized  by  the  inoculation 
of  either  tumor  or  normal  tissue.  He  looked  upon  the  transmutation 
as  a  proof  either  that  the  lost  inhibition  to  cell  growth  had  been  re- 
placed by  artificial  immunization,  or  else  that  the  normal  inhibitory 
powers  of  the  organism  might  be  increased  to  such  a  degree  that  the 
lawlessly  growing  cells  of  a  carcinoma  could  be  led  back  again  to  the 
more  orderly  growth  of  an  adenoma. 

But  Gierke,^  on  the  basis  of  a  research  carried  out  upon  turnors  of 
the  thyroid  gjand,  had  already  expressed  the  opinion  that  the  histologi- 
cal^appearance  of  a  growth  djd  not  of  itself  nermit  one  to_decide 
whether  the  neoplasm  were  benign  or  malignant.     There  occurred 

^  Berl.  Mill.  Woch.,  1907,  xliv,  419. 
^  Berl.  klin.  Woch.,  1907,  xliv,  1602. 

Zeitschrift  f.  Krebsforsch.,  1907-1908,  vi,  270. 
^  Miinch.  med.  Woch.,  1907,  liv,  1720. 
^Beitr.  zur  path.  Anat.,  etc.,  (Ziegler),  1908,  xliii,  338. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  126. 


I08  THE    TE_A.XSPLAXTED    TUilOR 

thyroid  tumors  exhibiting  a  structure  absolutely  benign  when  con- 
sidered from  the  histological  standpoint  which,  nevertheless,  were  not 
surpassed  in  mahgnancy  by  any  of  the  carcinomata.  Such  tumors 
must  be  acknowledged  as  carcinomata  whose  cells  had  retained  the 
capacity  for  more  advanced  differentiation.  Transitions  were  pro- 
vided by  tumors  possessing  in  some  parts  a  well-marked  carcinomatous 
structure  and  in  others  that  of  a  simple  goiter  as,  for  example,  in 
metastases  in  the  lungs  or  lymph  nodes.  Eberth  had  already  charac- 
terized this  condition  as  a  "change  for  the  better  "  but.  unfortunately, 
the  histological  "improvement"  did  not  necessarily  correspond  to  a 
biological  one ;  and  it  was  their  biological  behaAdor  alone  which  lent 
to  mahgnant  tumors  their  chief  significance  and  necessitated,  at  least 
in  principle,  the  maintenance  of  a  distinction  between  them  and  the 
benign  growths.  Exactly  the  same  conditions  were  to  be  found  in 
the  mammary  tumors  of  the  mouse,  and  hence  Gierke  concluded  that 
there  were  certain  interchangeable  relations  between  the  histological 
structure  and  the  biological  beha\'ior  of  a  tumor,  but  that  any  direct 
inference  from  one  to  the  other  could  be  made  only  with  great  caution. 
Murray^  beheved  that  an  experimentally  induced  increase  of  resist- 
ance, in  so  far  as  it  did  have  any  effect  on  the  structure  of  a  tumor, 
exerted  it  in  a  direction  opposite  to  that  indicated  by  Apolant  —  in 
the  direction,  that  is,  from  adenomatous  toward  alveolar  build.  He 
was  unable  to  subscribe  to  the  far-reaching  conclusions  of  Apolant, 
which,  as  an  explanation  of  increased  resistance,  postulated  a  direct 
influence  upon  fundamental  properties  of  the  tumor  cell  in  the  sense  of 
decreasing  its  mahgnancy.  The  histological  study  of  many  strains 
during  their  growth  in  normal  and  resistant  animals  had  sho^^m  that 
the  malignant  cell  possessed  an  inherent  cycUcal  variabihty  of  histologi- 
cal differentiation,  which,  however,  was  not  expressed  to  the  same  degree 
in  all  cases.  This  property  was  as  much  an  expression  of  the  cyclical 
growth  of  cancer  as  were  spontaneous  variations  in  prohferative 
energy,  but  since  no  connection  between  these  two  phenomena  had 
yet  been  discovered  they  must,  at  least  for  the  present,  be  looked  upon 
as  two  independent  properties  of  the  tumor  cell.  To  the  cychcal  varia- 
tions in  histological  appearance  there  could  be  superadded,  through 

^  Bed.  klin.  Wock.,  1909,  xlvi,  1520. 


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THE   TEANSPLANTED    TUMOR  lOQ 

the  induction  of  experimentally  increased  resistance,  structural  changes 
of  slight  degree,  such  as  a  tendency  to  assume  the  alveolar  type 
with  a  loss  of  the  characteristic  adenomatous  differentiation.  This 
relationship  could  be  explained  by  the  inhibition,  in  resistant  animals, 
of  the  stroma  reaction  induced  by  the  cancer  cell  in  normal  ones. 
It  was  clear  that  the  construction  of  a  perfect  adenomatous  con- 
dition required  an  intimate  relationship  between  parenchyma  and 
connective  tissue,  and  that  if  the  stimulus  of  the  cancer  cells  upon  the 
stroma  were  to  be  decreased  or  abohshed,  they  would  remain  in 
masses  and  the  growth  would  contain  a  minimum  of  connective  tissue. 
The  reappearance  of  acini  in  Apolant's  experiment  may  have  been 
due,  according  to  Bashford,^  to  the  comparison  of  an  old,  slowly  growing 
tumor  with  more  rapidly  growing  and  younger  controls." 

In  tlie  Stroma 

Bashford,  Murray,  and  Cramer,-  and  Apolant^  found  that,  as  a 
general  rule,  the  character  of  the  stroma  in  hemorrhagic  tumors  was 
preserved  during  propagation,  a  fact  which  Ehrlich  ^  attributed  to  a 
chemo tactic  power  resident  in  the  cells  of  the  parenchyma,  by  virtue 
of  which  they  were  enabled  to  attract  angioblasts.  On  the  other 
hand,  as  Bashford '"  has  observed,  the  hemorrhagic  character  of  the 
stroma  may  be  lost  or  diminished  during  continued  transplantation. 

An  extended  consideration  of  such  changes  as  this  may,  however, 
be  dismissed  as  unprofitable  while  there  remains  to  be  reviewed  the 
assumption  of  sarcomatous  properties  by  stroma  cells  previously 
benign. 

This  significant  deviation  was  first  observed  by  Ehrlich  and  Apolant^ 
in  a  transplantable  adeno-carcinoma  of  the  mouse,  in  the  tenth 
generation  of  which  there  were  found  two  growths  containing  both 
carcinomatous  and  sarcomatous  areas.  Exactly  at  what  point  the 
change  had  occurred  the  authors  were  unable  to  say,  but  it  must  have 

1  Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  191 1,  170. 

2  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  30. 
'  Verhandl.  d.  deutschen  path.  Gesellsch.,  1908,  late  Tagung,  7. 

*  Arb.  a.  d.  Kmigl.  Inst.f.  Exp.  Therap.,  1906,  Heft  i,  69. 

^  Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  191 1, 154. 

^  Berl.  klin.  Woch.,  1905,  xlii,  873. 


no  THE   TRANSPLANTED   TUMOR 

been  present  in  the  ninth  generation,  because  two  of  the  descendants 
were  of  a  mixed  character.  Those  of  the  first,  second,  and  sixth 
generations,  however,  were  pure  adeno-carcinomata. 

The  mixed  growths  contained  carcinoma  cell  nests  separated  from 
one  another  by  strands  of  large  spindle  cells  in  which  mitosis  was 
actively  progressing,  while  in  some  parts  of  the  sections  the  process  was 
so  advanced  that  the  carcinomatous  elements  had  disappeared  entirely. 
In  one  tumor  of  the  thirteenth,  and  in  all  those  of  the  fourteenth  and 
subsequent  generations,  no  trace  of  carcinoma  was  discoverable,  pure 
sarcoma  having  been  evolved  through  the  gradual  elimination  of  the 
epithelial  components.  The  growth  had  been  cultivated  as  far  as  the 
twenty-sixth  generation  without  showing  the  slightest  variation  from 
the  characteristic  structure  of  a  pure  spindle  cell  sarcoma. 

Two  explanations  were  advanced  to  account  for  the  transformation. 
An  alteration  in  the  chemistry  of  the  cancer  cell  was  conceivable,  in  the 
course  of  which  there  was  elaborated  a  material  possessing  the  power 
to  incite  connective  tissue  cells  to  malignant  growth.  This  hypothesis 
was  later  extended  by  Ehrlich  ^  to  include  and  explain  a  difference  that 
had  been  observed  between  the  grade  of  sarcoma  development  attained 
in  individual  mice  of  one  and  the  same  series.  He  suggested  that 
this  was  best  elucidated  by  assuming  that  the  predisposition  to  the 
growth  of  connective  tissue  varied  in  different  animals  as,  for  instance, 
certain  persons  were  more  prone  than  others  to  the  development  of 
keloids.  To  this  amendment,  however,  Russell  ^  objected  that  the  tumor 
with  which  he  himself  had  been  working  was  able  to  initiate  the 
sarcomatous  change  in  nearly  every  mouse  and  that  practically  all  of 
them  must,  therefore,  have  been  "keloid"  mice,  while  Jensen's  car- 
cinoma, which  had  probably  been  transplanted  into  more  mice  than 
any  other  tumor,  had  never  yet  happened  to  be  inoculated  into  a 
"keloid"  mouse. 

Ehrlich  and  Apolant's  alternative  explanation  for  the  sarcomatous 
change  was  that  repeated  transplantation  of  cancer  cells  and  connective 
tissue  evoked  a  proliferative  energy  in  the  cells  of  the  latter  which 
advanced  to  the  degree  of  malignancy. 

This  latter  hypothesis  was   excluded  by   Bashford,  Murray,    and 

^  Zeitschrift  f.  Krebsforsch.,  1907,  v,  64. 
^  Jour.  Path,  and  Bad.,  1910,  xiv,  374. 


THE   TRANSPLANTED   TUMOR  III 

Cramer  ^  on  the  ground  that  Jensen,  and  afterward  they  themselves, 
had  demonstrated  that  the  stroma  of  the  introduced  graft  always 
degenerated.  The  explanation  they  therefore  considered  to  be  at 
variance  with  the  facts. 

To  this  criticism  Ehrlich  and  Apolant  ^  answered  that  the  hypothesis 
in  question  did  not  in  the  sHghtest  degree  conflict  with  the  commonly 
recognized  fact  that  the  inoculated  stroma  usually  died  out.  In 
the  course  of  many  transplantations,  and  under  the  influence  of  the 
carcinoma,  it  might  occasionally  happen  that  the  stroma  cells  suffered 
a  transformation  which  allowed  them  to  remain  and  grow  Hke  those 
of  a  carcinoma. 

Bashford^  replied  that  the  authors  had  neglected  to  eliminate 
certain  sources  of  error,  and  until  that  were  accomplished  it  would 
be  impossible  to  decide  whether  the  growth  had  been  a  mixed  tumor 
from  the  beginning,  whether  an  infectious  granuloma  had  arisen  upon 
a  carcinoma,  or  whether  a  true  sarcoma  had  evolved  itself  from  the 
introduced  stroma  or  the  reaction  tissue  of  the  host.  That  a  sarcoma 
might  arise  during  the  transplantation  of  a  carcinoma  was,  a  priori, 
not  impossible. 

EhrKch  and  Apolant^  retorted  that  Bashford  had  never  had  under 
observation  a  tumor  of  reaUy  high  virulence,  and  that  in  this  respect  his 
experience  was  imperfect.  As  regarded  Bashford's  first  objection, 
the  authors  had  already  stated  that  neither  in  the  primary  growth 
nor  in  the  daughter  tumors  immediately  following  its  transplantation 
had  there  been  any  departure  from  the  usual  appearance  of  carcinoma 
of  the  mouse.'^  So  far  as  concerned  the  dift'erential  diagnosis  between 
granuloma  and  sarcoma,  the  most  eminent  pathological  judgment  in 
Germany  had  concurred  in  favor  of  the  latter ;  and,  furthermore,  such 
enormous  growth  energy  as  was  exhibited  by  the  tumor  under  discus- 
sion never  had  been  seen  in  an  infectious  granuloma. 

^  Bed.  klin.  Woch.,  1905,  xlii,  1434  (footnote).        ^Berl.  kliii.  Woch.,  1906,  xliii,  477. 

^  Bed.  klin.  Woch.,    1906,  xliii,  39  (footnote).         ^  Bed.  klin.  Woch.,  1906,  xliii,  668. 

5  When  Apolant  demonstrated  two  of  these  primary  tumors,  however  (Verhandl.  d. 
deidschen  path.  Gesellsch.,  1905,  9*^  Tagung,  168),  v.  Hansemann  said  that  he  had  found 
spindle  cells  in  the  stroma  of  one  of  them,  and  therefore  suggested  that  the  second  growth 
be  subjected  to  the  closest  scrutiny,  to  ascertain  whether  they  might  not  be  present  in 
other  areas.  But  Apolant  thought  that  the  existence  of  the  cells  described  by  v.  Hanse- 
mann would  hardly  warrant  one  in  calling  the  growth  a  mixed  tumor. 


112  THE   TRANSPLANTED   TUMOR 

The  diagnosis  of  sarcoma  was  once  again  defended  by  Apolant,^  on 
the  double  basis  of  cHnical  behavior  and  histology.  These  tumors  grew 
just  as  rapidly  as  they  had  before  the  change  took  place,  yielding 
growths  the  size  of  a  plum  within  three  weeks,  and  infiltrating  the  sur- 
rounding tissues  just  as  seriously.  The  histology  permitted  no  doubt  of 
their  sarcomatous  nature,  for  in  addition  to  the  typical  arrangement 
of  their  elements  they  presented  from  their  very  inception  a  number 
of  mitoses  not  exceeded  by  that  found  in  the  most  rapidly  growing 
mouse  carcinomata.  Metastatic  deposits,  however,  had  not  been 
discovered. 

Ehrlich  and  Apolant  ^  reported  two  further  instances,  the  first  of  which 
arose  between  the  twelfth  and  fourteenth  generations  of  an  alveolar 
carcinoma  which  had  originated  from  a  mixture  of  four  epithelial  tumors. 
Here  the  growth  energy  of  the  new  sarcoma  was  less  than  in  the  first 
case,  for  the  mixed  tumor  stage  persisted  through  ten  generations  (six 
months)  without  change.  The  second  case  occurred  during  the  trans- 
plantation of  one  of  the  four  epithehal  growths  just  mentioned.  Little 
alteration  had  been  observed  up  to  the  fortieth  generation,  but  at 
that  point  an  increased  cellularity  of  the  stroma  made  its  appearance, 
although  sarcoma  development  could  not  be  indubitably  estabhshed. 
It  was  confirmed,  however,  in  the  sixty-eighth  generation,  after  two 
years  and  a  half  of  propagation.  It  seemed  significant  to  the  authors 
that  the  sarcomatous  change  arose  only  in  the  later  generations,  for 
although  it  had  occurred  relatively  early  in  the  first  case,  after  only  nine 
months  of  transplantation,  in  the  second  and  third  cases  it  did  not 
supervene  until  after  two  and  two  and  a  half  years  respectively.  This 
fact  explained  why  the  transformation  had  not  been  observed  more 
frequently,  for  at  the  time  of  writing  only  the  Jensen  tumor  had  been 
cultivated  over  a  period  of  time  at  all  comparable  to  these.  Its  viru- 
lence, however,  was  much  lower  than  that  of  the  Frankfort  tumors. 
In  later  papers  the  authors  returned  to  this  question  of  the  relation 
between  virulence  and  sarcoma  development,  and  were  inchned  to 
attribute  great  importance  to  virulence  in  the  initiation  of  the  trans- 
formation. 

That  the  length  of  time  during  which  a  tumor  had  been  under 

1  Arb.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  56. 

2  Berl.  klin.  Woch.,  1906,  xliii,  38. 


THE    TRANSPLANTED  TUMOR  II3 

cultivation  did  not  deserve  the  importance  at  first  ascribed  to  it  they 
were  able  to  record  in  the  following  year,  after  they^  had  discovered 
one  instance  in  which  sarcoma  development  had  certainly  occurred  in 
the  spontaneous  tumor,  and  a  second  where  such  a  change  had  in  all 
probability  taken  place  there.  A  similar  example  was  later  recorded 
by  Haaland,^  in  which  a  spontaneous  growth,  removed  by  operation, 
was  found  to  consist  of  a  central  carcinomatous  part  surrounded  by 
a  band  of  spindle  cell  sarcoma. 

Useful  reviews  of  the  cases  of  sarcoma  development  which  have 
been  observed  at  the  Frankfort  laboratory  have  been  given  by  both 
EhrHch^  and  Apolant.^ 

Loeb  ^  described  a  primary  non-metastasizing  adeno- carcinoma  in  the 
submaxillary  gland  of  a  female  Japanese  mouse  from  six  to  eight  months 
old.  The  tumor  was  of  uniformly  epithelial  structure  and  belonged 
to  the  glandular  type.  It  was  possessed  of  ducts  and  alveoli ;  the 
lumina  of  the  latter  contained  colloid  material,  and  the  epithelial 
elements  were  supported  by  a  diffuse  connective  tissue.  Inoculation 
was  successful  in  Japanese  mice  but  failed  in  those  of  the  white  variety. 
In  one  of  two  surviving  Japanese  mice  a  few  slowly  growing  nodules 
were  found  fifty-eight  days  after  inoculation,  one  of  which,  removed  a 
few  days  later  by  operation,  proved  to  be  a  spindle-cell  sarcoma.  When 
the  animal  was  found  dead  ninety  days  after  inoculation  and  twenty- 
six  days  after  the  excision  of  the  nodule,  there  was  a  recurrence  which 
had  grown  rapidly  and  which  consisted  almost  exclusively  of  pure 
sarcoma,  and  in  addition  a  large  glandular  tumor  in  which  sarcoma 
was  developing  at  one  point.  The  tumors  of  the  second  mouse,  glan- 
dular growths  with  some  sarcomatous  elements  in  them,  were  used  for 
transplantation  ninety-three  days  following  inoculation.  They  were 
ingrafted  into  six  mice,  one  of  which  was  found  later  to  have  developed 
a  pure  sarcoma,  while  the  growths  in  four  of  the  other  mice  were  mixed. 

^  Berl.  klin.  Woch.,  1907,  xliv,  1399. 

^Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  191 1,  19. 
^  Zeitschrift  f.  Krebsforsch.,  1907,  v,  62. 

^  Handbiich  der  pathogenen  Mikroorganismen,  Kolle  and  Wassermann,erster  Erganzungs 
band,  1906,  452. 

Zeilschrift  f.  allg.  Physiol.,  1909,  ix,  Sammelreferat,  96. 
^  Univ.  Pennsylvania  Med.  Bidl.,  igo6,  xix,  113. 

Berl.  klin.  Woch.,  1906,  xliii,  798. 


114  ^^^^    TEAXSPLAMTED   TUMOR 

The  sixth  had  two.  one  glandular  and  one  a  pure  sarcoma.  In  the 
second  generation  the  sarcoma  was  in  excess  of  the  carcinoma,  as  it 
had  been  in  Ehrhch  and  Apolants  hrst  case.  Because  the  chances 
of  further  transplantation  were  excluded  by  a  shortage  of  Japanese 
mice  the  experiment  was  perforce  terminated. 

For  the  appearance  of  the  sarcoma  Loeb  offered  three  explanations 
—  that  the  tumor  was  originally  a  mixed  tumor,  that  the  sarcoma 
was  derived  from  the  connective  tissue,  or,  finally,  that  a  transforma- 
tion of  glandular  into  spindle  ceU  tissue  had  taken  place.  The  nxst 
he  thought  improbable,  and  left  open  the  choice  between  the  second 
and  the  third.  If  one  accepted  the  second  it  would  be  possible  to 
eliminate  the  theon.-  that  sarcoma  development  was  the  result  of 
repeated  inoculation  of  stroma,  because  the  change  had  occurred  in 
the  first  generation.  It  seemed  most  probable  that  the  sarcomatous 
transformation  was  the  result  of  a  stimulus  of  unknown  nature  exerted 
upon  the  stroma  by  the  carcinomatous  moiet}'  of  the  tumor. 

In  a  later  paper  he-  said,  in  discussing  the  third  explanation,  that  it 
had  been  impossible  to  find  any  evidence  of  transition  stages  between 
adeno-carcinoma  and  sarcoma  in  those  areas  where  sarcomatous 
tissue  was  present.  The  article  concluded  with  a  reaffirmation  of 
the  h^-pothesis  that  the  probable  cause  of  sarcoma  development  was 
a  stimulus  exercised  upon  the  surrounding  connective  tissue  by  the 
ceUs  of  the  carcinoma. 

Haaland,^  investigating  the  occurrence  of  metastases  in  the  second 
of  EhrKch's  sarcoma  strains,  found  that  microscopic  nodules  occurred 
in  the  lungs  of  60%  of  his  mice  with  tumors  that  were  from  fourteen 
to  forty  days  old.  The  importance  of  this  obserx^ation  lay  in  the  fact 
that  the  method  by  which  a  tumor  spread  through  the  organism  was 
a  sound  .criterion  for  the  distinction  between  true  mahgnant  growths 
and  the  infectious  granulomata.  By  examining  serial  sections 
Haaland  could  show  that  the  metastatic  emboh  reached  the  lungs 
through  the  blood  stream,  determining  their  relation  to  the  vessels 
by  the  aid  of  Weigert's  elastic  tissue  stain.  For  the  investigation 
of  the  stroma  either  van  Gieson's  or  I^Iallorx^'s  method  was  employed. 

^  Zeitsckrift  f.  Krebsforsch.,  1908-1909,  \"ii,  loi. 
*  Berl.  klin.  Woch.,  1906,  idiii,  11 26. 
Zeitschrijt  f.  Krebsforsch.,  1907,  v.  122. 


THE    TEANSPLANTED   TUMOR  I15 

It  was  probable  that  a  considerable  number  of  emboli  were  destroyed, 
or  at  least  did  not  grow,  for  he  fomid  them  occasionally,  as  Sclnmdt^ 
had  described  them  in  human  lungs,  surrounded  by  collections  of 
round  cells  and  leucocytes,  and  the  seat  of  regressive  changes.  The 
majority,  however,  were  in  active  growth,  filhng  and  distending  the 
lumina  of  the  vessels ;  in  this  intravascular  stage  there  was  no  sign 
of  reaction  either  in  the  vessel  wall  or  the  surrounding  lung  tissue. 
In  their  further  development  these  emboh  assumed  an  infiltrative 
growth  during  which  their  elements  rapidly  penetrated  the  wall  and, 
infiltrating  the  neighboring  tissues,  surrounded  the  vessels  with  a 
mantle  of  tumor  cells.  Larger  nodules  were  thus  evolved  which 
entirely  destroyed  the  lung  parenchyma  and  spared  only  the  elastic 
tissue.  While  the  stroma  of  these  tumors  was  sparse,  and  in  most 
cases  hardly  recognizable  in  the  early  stages,  there  were  a  few  instances 
in  which  MaUory's  stain  would  demonstrate  a  few  very  dehcate, 
sinuous,  blue-stained  fibrils  between  the  individual  cells,  even  before 
the  penetration  of  the  vessel  wall.  In  the  later  stages,  when  the  wall 
had  been  broken  through,  the  histological  picture  was  compKcated 
by  the  fact  that  portions  of  the  connective  tissue  of  the  lung,  and  of 
that  accompanying  the  blood  vessels,  had  persisted  and  were  partici- 
pating in  forming  the  stroma  of  the  new  nodule.  But  even  here  stroma 
development  remained  within  certain  bounds,  being  limited  to  the  re- 
production of  a  few  isolated  fibrils  between  the  individual  tumor  cells. 

Liepmann-  had  under  observation  a  mouse  carcinoma  which,  at 
the  eighth  transplantation,  had  assumed  the  character  of  a  carcinoma 
sarcomatodes,  although  as  far  as  the  fifth  generation  the  typical 
carcinomatous  structure  of  the  spontaneous  tumor  had  been  retained. 

Bashford,  Murray,  and  Haaland  ^  described  the  appearance  of 
sarcoma  during  propagation  of  a  mammary  adeno-carcinoma  ("37  ")  of 
the  mouse.  The  transformation  occurred  in  the  seventh  and  eighth 
generations  in  two  strains,  one  of  which  had  always  been  transplanted 
with  the  needle,  and  the,  other,  after  the  fourth  generation,  with  the 
syringe.  Seven  tumors  out  of  ten  in  the  seventh  generation  were 
transplanted,  giving  rise  to  the  eighth.     The  usual  systematic  examina- 

1  Die  V erhreitimgswege  des  Carcinoms,  etc.,  Jena,  1903,  41. 
^  Miinch.  med.  Woch.,  1907,  liv,  1345. 
^  Berl.  klin.  Woch.,  1907,  xliv,  1238. 


Il6  THE    TEANSPLANTED    TUMOR 

tion  of  the  growths  in  each  generation  had  revealed  no  change  in  the 
stroma  before  the  seventh.  At  this  point  two  again  were  unchanged, 
while  in  two  others  there  was  a  slight  increase  in  the  amount  and 
cellularity  of  the  stroma,  and  one  of  them  contained  a  small  area  of 
spindle  cells.  In  the  remaining  three  the  stroma  had  increased 
greatly  in  amount  and  now  formed  broad  bands  of  elongated  cells 
lying  among  the  carcinomatous  elements.  Transplantation  of  this  gen- 
eration resulted  in  a  yield  of  twenty- two  tumors,  in  twenty  of  which 
there  were  found  spindle  cells  arranged  in  bands  and  undergoing  rela- 
tively rapid  division.  The  examination  of  grafts  at  short  intervals  after 
transplantation  showed  conclusively  that  the  stroma  did  not  die  out 
as  it  had  in  the  previous  generations,  but,  on  the  contrary,  that  it 
remained  alive,  and,  moreover,  possessed  the  power  of  independent 
proHferation.  In  older  tumors  of  the  eighth  and  in  those  of  the 
ninth  and  tenth  generations,  the  carcinomatous  portions  were  sur- 
rounded by  halos  of  clear  polymorphous  cells,  larger  than  those  of 
the  carcinoma  and  distinguished  from  them  by  their  lightly  stained 
protoplasm.  That  they  were  not  of  epithehal  origin  was  certain.  In 
fact,  one  could  find  all  transitional  stages  between  them  and  the 
typical  spindle-shaped  stroma  cells,  which  appeared  to  be  a  more 
highly  differentiated  form  of  the  cell  now  under  discussion.  Although 
the  zones  just  mentioned  gave  the  impression  of  a  reaction  tissue 
composed  of  elements  newly  arisen  from  those  of  the  host,  the  study 
of  young  grafts  demonstrated  that  the  clear  cells  did  not  die  out 
after  transplantation,  but  were  able  to  proliferate  and  to  produce  sar- 
coma. The  authors  believed  that,  although  endowed  with  the  power 
of  independent  growth,  these  cells  had  not  yet  lost  entirely  their  old 
relation  to  those  of  the  carcinoma,  but  had,  on  the  contrary,  remained 
sensitive  to  influences  emanating  from  these  elements  and  were 
accordingly  arranged  about  the  alveoli  in  the  manner  of  the  old 
stroma.  Only  the  stroma  cells  far  removed  from  the  carcinoma  were 
exempt  from  this  influence  and  able  to  differentiate  characteristically 
into  bands  of  spindle  cells. 

As  the  stroma  of  three  tumors  in  the  same  series  showed  sarcomatous 
transformation,  it  seemed  more  Hkely  that  some  special  stimulus  over 
and  above  the  ordinary  stroma-forming  stimulus  had  been  exerted 
upon  the  fibroblasts  by  the  carcinoma  cells,  than  that  the  sarcomatous 


J.  R.  Ford.  del. 

3ne  of  four  growths  (41  days  old)  of  Series  D,  7th  generation  of  tumor  37,  which  showed  first  cases 
of  sarcoma  development.  Abundant  cellular  interstitial  connective  tissue,  consisting  of  large 
spindle  cells,  runs  between  the  islands  of  acinous  parenchyma  throughout  the  whole  tumor.     X  -^. 


m>€^ 


(^ 


e:§^-> 


<S^  g^-^T)     (225  z^-^Q^ 


Sv#^      €Sj 


? 


o 


o 


-^^v^© 


«sz> 


J^.  iS.  Fortf,  del. 


Iixed  tumor  of  the  loth  generation,  23  days  old.     Broad  bands  of  sarcomatous  tissue  containing 
mitoses,  and  separating  the  acini  of  the  carcinoma.     X  ^^. 


THE    TRANSPLANTED   TUMOR 


117 


change  had  been  initiated  through  any  particular  attribute  of  the  mice 
in  which  it  had  taken  place. 

The  stroma,  now  able  to  proHferate  independently,  was  no  longer 
subser\'ient  to  the  needs  of  the  epithehal  parench}Tna  in  the  matter 
of  pro\dding  nutrition  for  its  cells,  and,  indeed,  it  even  seemed  as 
though  the  carcinomatous  part  of  the  tumor  was  isolated  from  the 
blood  vessels  by  the  halos  of  clear  cells.  Whether  or  not  this  explained 
the  disappearance  of  the  carcinomatous  elements,  the  contrast  in  size 
between  the  succulent  cells  of  the  sarcomatous  stroma  and  those  of 
the  epithelial  parench}Tna  was  striking.  Both  the  nuclei  and  proto- 
plasm of  the  latter  appeared  to  diminish  in  size,  while  mitoses  became 
less  and  less  frequent  as  the  transformation  of  the  stroma  proceeded, 
until  finally  complete  disappearance  supervened. 

An  attempt  was  made,  with  a  fairly  successful  outcome,  to  hasten 
''purification"  of  the  tumor  by  introducing  it  into  mice  resistant  to 
carcinoma.  One  tumor  showing  a  pronounced  decrease  in  the  amount 
of  carcinoma  was  obtained  from  ten  inoculations.  In  the  next  trans- 
plantation, which  was  made  into  normal  mice,  only  traces  of  carcinoma 
could  be  discovered,  and  in  the  next  succeeding  one  a  pure  sarcoma 
was  found.  In  none  of  the  controls  was  there  obtained,  within  the 
same  period,  a  tumor  of  purely  sarcomatous  type. 

The  quantitative  relation  between  carcinoma  and  sarcoma  varied 
somewhat  from  tumor  to  tumor,  but  as  a  rule  the  progress  of  the 
sarcoma  was  uninterrupted,  although  in  isolated  cases  the  carcinoma 
appeared  to  obtain  the  mastery,  so  that  the  regaining  of  a  pure  car- 
cinoma seemed  possible  of  achievement. 

The  authors  suggested  two  ways  of  accounting  for  the  appearance 
of  sarcoma.  Either  the  tumor  was  from  the  start  a  mixed  one,  or  its 
cells  had  the  power  to  exert  a  specific  stimulus  upon  the  connective 
tissue,  causing  its  elements  to  become  capable  of  continued  prohfera- 
tion  and  thereby  transplantable.  Systematic  study  of  early  stages 
led  Bashford  and  his  associates  to  accept  the  latter  explanation,  in 
doing  which  they  were  in  agreement  with  the  hypothesis  advanced  by 
Ehrhch  and  Apolant.  None  of  the  three  factors,  length  of  propaga- 
tion period,  virulence,  or  histological  structure  of  a  tumor,  seemed  to 
be  of  moment  in  determining  whether  the  growth  would  or  would 
not  be  able  to  induce  sarcomatous  transformation. 


Il8  THE   TRANSPLANTED    TUMOR 

Loeb  ^  also  was  of  the  opinion  that  it  was  not  necessary  for  the 
carcinoma  to  be  possessed  of  any  particularly  high  degree  of  virulence. 

In  the  rat,  Lewin  ^  observed  sarcomatous  transformation  in  the 
fifth  generation  of  a  keratinizing  adeno-carcinoma,  and  was  inclined 
to  consider  that  endothelial  cells  were  the  ancestors  of  the  sarcoma. 

Orth,^  who  examined  Lewin's  preparations,  was  not  convinced 
that  the  tumors  had  actually  undergone  a  sarcomatous  change,  and 
expressed  the  behef  that  the  new  cells  were  those  of  ordinary  granu- 
lation tissue. 

Sticker  ^  advanced  the  supposition  that  many  cases  of  so-called 
sarcoma  development  were  either  the  issue  of  the  inoculation  of  a  mixed 
tumor,  or  else  represented  the  simultaneous  occurrence  of  a  trans- 
plantable carcinoma  and  a  spontaneous  sarcoma  in  the  same  animal. 

Haaland^  described  the  change  in  other  strains  of  the  tumor  re- 
ported by  Bashford,  Murray,  and  Haaland,  pointing  out  that 
sarcoma  development  had  hitherto  taken  place  so  unexpectedly  that 
observations  had  of  necessity  been  made  long  after  the  actual  occur- 
rence of  the  transformation.  The  material  available  had,  therefore, 
been  incomplete.  The  present  case,  however,  was  encountered  under 
much  more  favorable  auspices,  for,  as  the  primary  growth  had  been 
examined  on  two  occasions  and  sections  from  every  tumor  in  the  fol- 
lowing generations  were  at  hand  for  histological  survey,  there  were 
no  gaps  in  the  continuity  of  the  earlier  material.  Moreover,  it  had 
been  possible  to  supplement  the  morphological  data  thus  obtained  with 
a  comparison  of  the  biological  peculiarities  of  different  strains,  be- 
cause the  chnical  behavior  of  all  the  tumors  had  been  recorded  on  a 
series  of  charts.  In  addition  to  this  investigation  of  general  histologi- 
cal and  biological  characters,  the  processes  in  play  at  short  intervals 
after  transplantation  had  been  examined,  and  the  beha\dor  of  the 
tumor  at  any  period  after  the  moment  of  inoculation  could  thus  be 
compared  with  its  behavior  at  any  later  stage.  Finally,  the  carci- 
noma had  not  been  lost   during  the  development  of    the  sarcoma, 

1  Deut.  med.  Woch.,  1908,  xxxiv,  25. 
^  Zeitschrift  f.  Kre.bsforsch.,  1907-1908,  vi,  273. 
^  Zeitschrift  f.  Krehsforsch.,  1907-1908,  vi,  431. 
^  Zeitschrift  f.  Krehsforsch.,  1907-1908,  vi,  431. 
^  Jour.  Path,  and  Bad.,  1908,  xii,  437. 
Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  175. 


.?    w  /T.  ^  ^'.   ^  . 


Iff**"        V 


J.  R.  Ford,  del. 

24-day-old  mixed  growth  from  9th  generation  of  tumor  37,  to  show  halos  aroimd  healthy  alveoli. 

X  circa  ^¥^. 


THE    TEANSPLANTED    TUMOR  II9 

and  ten  separate  strains  of  purely  epithelial  tumors  had  been  pre- 
served. 

Haaland  and  his  colleagues  had  been  enabled,  therefore,  to  make 
an  exhaustive  study  of  the  question  from  every  standpoint — the 
histology  of  the  primary  growth,  the  progressive  advance  of  the  sar- 
comatous change,  the  condition  of  the  stroma  in  old  tumors  of 
carcinomatous  strains  as  well  as  in  new  grafts,  and  the  biological 
characteristics  of  carcinomatous,  mixed,  and  sarcomatous  strains. 

Although  the  mother  material  of  the  four  tumors  in  which  sarcoma 
development  had  arisen  had  been  examined  in  the  hope  that  the  route 
taken  by  the  stroma  cells  could  be  retraced,  the  change  seemed  to  have 
been  a  sudden  one,  and  no  indication  could  be  discovered  of  the  man- 
ner in  which  it  had  been  initiated. 

The  progressive  advance  of  the  transformation  took  place  by  an 
increase  of  spindle  cell  tissue  from  one  generation  to  the  next,  and 
the  alveoH  became  more  widely  separated  from  one  another  in  con- 
sequence, often  showing  slight  necrotic  changes  due  to  impairment  of 
nutrition.  The  next  step  was  the  interpolation  of  an  intermediate 
period  where  for  several  generations  the  spindle  elements  were  replaced 
by  polymorphous  cells,  and  as  a  constant  and  characteristic  feature 
of  this  stage  lightly  staining  and  extremely  polymorphous  elements 
collected  about  the  carcinomatous  acini,  forming  halos  sharply  de- 
marcated from  the  latter  on  their  inner  circumferences,  but  shading 
off  gradually  into  the  sarcomatous  stroma  on  the  outer.  The  halos 
varied  from  a  single  row  of  cells  to  the  more  usual  width  of  several 
layers,  and  the  nuclei  were  very  large  and  sometimes  multiple.  Often 
the  nuclei^ were  of  the  true__gian^t>'pe,  verv^rich  irLxhrmnatin.  As 
long  as  any  epithelial  components  remained  in  the  tumors,  so  long 
did  polymorphism  persist,  but  with  the  entire  disappearance  of  the 
carcinomatous  cells  those  of  the  sarcoma  resumed  their  primary 
t>^ical  spindle  shape. 

What  was  the  derivation  of  these  Hghtly  staining  polymorphous 
cells  ?  The  idea  of  an  epithehal  origin  Haaland  felt  unable  to  enter- 
tain and,  as  they  prohferated  after  transplantation,  they  could  not 
be  the  elements  of  ordinary  granulation  tissue.  It  seemed  most  prob- 
able that  they  did  not  originate  from  the  connective  tissue  of  the  new 
host,  but  that  they  were  derived  from  preceding  sarcoma  cells  and 


120  THE    TRANSPLANTED    TUMOR 

transferred  as  such  with  the  graft,  and  this  explanation  was  made  even 
more  plausible  by  the  discovery  throughout  the  body  of  growing 
metastases  made  up  of  similar  cells. 

The  alveoh  that  were  surrounded  by  halos  very  often  showed  central 
necrosis,  ordinarily  a  rather  rare  occurrence  in  the  alveoH  of  the  tumor 
under  discussion.  These  degenerative  changes  Haaland  referred  to 
the  fact  that  no  trace  of  capillaries  could  be  found  inside  the  halos, 
and  the  cells  of  the  latter  thus  seemed  to  be  interposed  between  the 
alveoh  and  the  capillaries  of  the  stroma. 

The  sarcomata  of  this  strain  had  a  greater  initial  rapidity  of  growth 
than  the  carcinomata  and,  on  the  whole,  gave  a  higher  percentage  of 
growing  tumors,  although  spontaneous  absorption  was  of  very  fre- 
quent occurrence.  Their  power  of  infiltrative  growth  much  exceeded 
that  usually  evinced  by  the  carcinomata,  and  they  metastasized 
readily,  producing  secondary  growths  in  the  lungs,  heart,  liver,  kidney, 
spleen,  and  lymph  nodes. 

Mixed  growths  tended  to  become  pure  sarcomata,  but  the  process 
required  a  certain  length  of  time  and  seemed  to  occur  independently 
of  the  rapidity  of  passage  from  host  to  host ;  and  while  the  disappear- 
ance of  the  epithehal  part  of  the  tumor  was  generally  accompUshed 
first  in  the  center,  the  rate  at  which  the  process  went  on  in  the  different 
portions  was  variable.  To  see  whether  the  transformation  were  a 
sudden  one  Haaland  investigated  old.  and  young  growths  from  strains 
in  which  the  change  had  occurred,  as  well  as  from  others  which  had 
been  consistently  free  from  it.  In  all  the  later  cases  of  sarcoma 
development  he  found  the  first  alterations  at  the  center  of  the  carci- 
nomatous tumor,  and  here  sclerotic  lesions  were  habitually  present, 
often  accompanied  by  more  or  less  cellularity  of  the  stroma.  The 
sarcomatous  change  suggested  in  some  cases  a  process  similar  to  this, 
although  enhanced  in  degree.  It  was  not  suddenly  gained,  but  ap- 
peared to  be  a  gradual  acquisition,  the  power  of  continuous  growth 
and  the  rate  of  proliferation  becoming  more  advanced  in  its  later 
stages.  The  condition  seemed  to  be,  on  the  whole,  the  result  of  a 
gradual",  fluctuating  evolution. 

The  dependence  of  sarcoma  development  upon  virulence,  as  upheld 
by  EhrUch  and  Apolant,  was  not  a  phenomenon  of  universal  distri- 
bution, for  in  the  present  case  the  tumor  was  one  of  rather  slow  growth. 


THE   TRANSPLANTED    TUMOR 


121 


OOOQOOOoOOOpQQQO    O    O 


122  THE    TR-\XSPLAXTED    TUMOR 

Albrecht  and  Hecht  ^  confessed  that  they  had  been  unable  either 
to  initiate  or  to  influence  the  transformation  of  carcinoma  into  sar- 
coma. 

Russell.-  during  the  propagation  of  a  recurrent  spontaneous  hemor- 
rhagic mammary  adeno-carcinoma  of  the  mouse,  observed  the  assump- 
tion by  its  stroma  of  the  biological  and  morphological  characters  of 
sarcoma.  The  determining  factor  appeared  to  be  continuous  prolifer- 
ation in  one  animal  for  about  tifty  days,  for  rapid  passage,  that  is,  the 
transplantation  of  the  tumor  at  interA'als  of  about  thirty  days  or 
less,  preserved  the  purely  carcinomatous  character  of  the  growth. 
Once  the  sarcomatous  change  had  occurred  it  tended  progressively 
toward  the  entire  ehmination  of  the  carcinomatous  component,  and 
the  tumors  could  then  be  pro_pagated  indefinitelv  as  pure  sarcornata. 
Upon  the  initiation  of  the  transformation  there  was  no  change  in  the 
speed  of  growth,  and  tumors  which  had  been  cultivated  through 
one  or  more  generations  as  mixed  growths  retained  the  rate  of  the  pure 
carcinomata.  But  T\-ith  the  disappearance  of  the  epithehal  elements 
the  rate  of  development  increased  greatly,  whence  Russell  suggested 
that  they  might  be  capable  of  exerting  a  restraining  influence  upon 
the  proliferation  of  the  sarcomatous  areas. 

Although  the  sarcomata  were  of  rapid  growth  the}'  were  ver\'  prone 
to  spontaneous  absorption,  and  mice  in  which  this  had  taken  place 
were  resistant  to  the  inoculation  of  the  purely  carcinomatous  strains 
of  the  tumor. 

As  to  the  explanation  of  the  transformation  the  author  was  in  entire 
agreement  with  pre\'ious  observ^ers,  be^e^'ing  that  it  was  induced  in 
the  connective  tissue  cells  of  the  host  by  the  parench^mia  of  the 
epithehal  tumor. 

The  change  in  the  stroma,  which  was  generally  unicentric.  began 
toward  the  middle  of  the  growth  in  an  area  containing  a  relatively  enor- 
mous number  of  mitoses,  and  of  such  small  size  as  to  suggest  ver}'  recent 
origin.  In  point  of  time  the  transformation  usually  occurred  between 
the  flfty-fifth  and  sixtieth  days,  and  among  one  hundred  tumors  ex- 
amined only  four  or  five  showed  no  change  before  the  sixtieth  day, 

1  Coitralbl.  f.  allg.  Path.,  etc.,  1909,  xx,  1039. 

Wien.  klin.  Woch.,  1909,  xxii,  1740. 
^  Jour.  Path,  and  Bad.,  1910,  xiv,  344. 


THE    TRANSPLANTED    TUMOR  1 23 

while  one  had  advanced  to  pure  sarcoma  at  the  end  of  this  period. 
The  length  of  time  required,  however,  was  not  uniform,  for  while  in 
some  series  the  onset  of  the  sarcomatous  alteration  could  not  be  de- 
tected until  after  seventy  days,  in  others  the  change  was  present  even 
after  thirty-eight.  That  the  variation  was  not  due  to  individual  dif- 
ferences in  the  mice  was  proved  by  the  fact  that  the  initiation  of  the 
transformation  was  uniform  for  all  those  of  any  given  series.  A  stay 
of  longer  than  sixty  days  in  one  animal  was  difficult  to  secure  —  other- 
wise each  tumor  would  doubtless  have  progressed  to  the  stage  of  pure 
sarcoma. 

A  further  case  of  sarcoma  development  was  recorded  by  Stahr,^ 
affecting  certain  of  the  tumors  in  the  ninth  generation  of  a  fissure- 
forming  carcinoma.  Stahr's  observations  differed  somewhat  from 
those  of  Haaland  and  Russell  as  regarded  the  point  at  which  the 
change  began,  in  that  while  these  authors  had  recorded  its  first  appear- 
ance in  the  middle  of  the  tumor,  Stahr  found  it  earhest  at  the  periphery. 
He  agreed  with  Haaland,  however,  that  the  transformation  was  in 
some  way  connected  with  a  low  power  of  growth  on  the  part  of  the 
carcinoma  cells,  and  suggested  that  possibly  it  might  be  set  going 
through  the  agency  of  materials  elaborated  by  their  death. 

Clunet  ^  discovered  still  another  instance  of  sarcomatous  change 
in  a  growth  belonging  to  the  third  generation  of  a  malignant  mam- 
mary cyst-adenoma  of  the  mouse,  where  the  transition  was  complete 
in  every  tumor  of  the  sixth  generation.  Since  then  the  growth, 
which  had  reached  the  thirty-eighth  generation,  had  retained  its  sar- 
comatous character  unaltered.  The  maHgnancy  of  the  newly  pro- 
duced tissue  was  manifest  not  only  from  its  histology,  but  from  its 
clinical  behavior,  proliferation  continuing  indefinitely  and  leading  to 
death  from  cachexia.  Furthermore,  the  tumors  recurred  after  opera- 
tive removal,  infiltrated  the  surrounding  tissues,  and  produced  meta- 
static deposits  in  the  lungs. 

In  discussing  the  -  cause  of  the  mutation,  Clunet  eHminated  any 
chance  that  the  primary  tumor  had  been  a  carcinoma  sarcomatodes, 
and  accepted  a  mahgnant  change  in  the  stroma  as  the  most  probable 
explanation.     He  agreed  with  Haaland's  observations  on  the  absence 

1  Centralbl.  f.  allg.  Path.,  etc.,  1910,  xxi,  108. 

^  Reckerches  exp.  sur  les  Tumeurs  malignes,  Paris,  1910,  53. 


124  THE    TRANSPLANTED   TUMOR 

of  any  connection  between  tumor  virulence  and  sarcoma  development, 
for  in  the  first  six  generations  of  the  tumor,  while  the  sarcomatous 
change  was  being  initiated,  the  percentage  of  takes  had  been  low  and 
negative  inoculations  or  spontaneous  regressions  frequent.  As  in 
Russell's  experience,  the  power  of  growth  increased  rapidly  after 
the  epithehal  components  had  disappeared. 

CULTIVATION    OF    CELLS    IN   VITRO 

One  of  the  disadvantages  of  the  ordinary  method  of  investigating 
cancer  was  the  irregularity  inherent  in  the  soil  where  the  tumor  cells 
were  grown  and  in  which,  therefore,  they  had  to  be  studied.  Follow- 
ing the  lead  of  Harrison,^  who  showed  that  the  nerve  tissues  of  the 
frog  embryo  could  be  grown  in  lymph  outside  the  body,  other  ob- 
servers have  applied  the  method,  with  certain  modifications,  to  the 
cultivation  of  the  cells  of  various  normal  tissues  as  well  as  those  of 
tumors. 

The  use  of  lymph,  however,  proved  inconvenient  for  several  reasons, 
and  Burrows  ^  substituted  plasma,  which  he  obtained  from  blood 
that  had  been  centrifugalized  at  a  low  temperature  in  paraffined  tubes. 
In  the  opinion  of  Carrel  and  Burrows  ^  the  pure  plasma  thus  obtained 
was  much  superior  to  oxalated  plasma,  which  could,  nevertheless, 
be  used  in  cases  of  necessity.  The  authors  described  two  types  of 
culture  —  the  small  hanging  drop,  and  the  large  plate  culture.  In 
making  the  former,  one  or  two  fragments  of  the  tissue  which  it  was 
desired  to  cultivate  were  transferred  to  a  cover-glass  and  quickly 
immersed  in  a  drop  of  plasma,  which  was  spread  out  in  a  thin  layer  be- 
fore the  occurrence  of  coagulation.  The  cover-glass  was  then  inverted 
over  a  hollow  shde  to  which  it  was  sealed  with  paraffin  to  prevent  evap- 
oration, and  the  preparation  immediately  transferred  to  the  incubator. 
Large  plate  cultures  were  made  by  spreading  fragments  of  tissue  in  a 
thin  layer  over  the  surface  of  a  large,  black  glass  plate,  and  covering 

^  Proc.  Soc.  Exp.  Biol,  and  Med.  1906-1907,  iv,  140. 

Anat.  Record,  1908,  ii,  385. 

Jour.  Exp.  Zool.,  1910,  ix,  787. 
^  Jour.  American  Med.  Assoc,  1910,  Iv,  2057. 
^  Jour.  Exp.  Med.,  191 1,  xiii,  387. 


THE    TRANSPLANTED    TUMOR 


125 


them  quickly  with  plasma.  As  soon  as  coagulation  appeared  the 
plates  were  put  into  glass  boxes  containing  moist  cotton  to  preserve 
the  proper  humidity,  and  the  boxes  were  sealed  with  paraffin  and  kept 
in  the  incubator  in  such  a  position  as  to  allow  the  fluid  products  of  the 
culture  to  drain  to  the  bottom.  The  most  careful  asepsis  was,  of 
course,  necessary  throughout  the  procedure. 

For  the  study  of  the  cultures,  a  warm  stage  was  employed  on  the 
microscope.  Growing  cells  at  the  edge  appeared  as  fusiform  or  polyg- 
onal bodies,  the  cytoplasm  of  which  was  filled  with  refractile  granules. 
Often  the  movements  of  the  Hving  cells,  their  modification  in  shape, 
and  the  division  of  their  nuclei  could  be  readily  observed.  Cultures 
could  be  fixed  and  stained  by  removing  the  cover-glass  with  its  ad- 
herent tissue  to  appropriate  solutions  or,  in  case  the  plasmatic  medium 
was  thick  and  the  cells  had  grown  in  many  planes,  serial  sections  of  the 
hardened  cultures  could  be  made. 

Carrel  ^  reported  in  a  subsequent  contribution  that  cell  division  had 
been  observed  in  cultivated  tissues  washed  and  placed  in  fresh 
media,  as  long  as  thirty-one  days  after  their  removal  from  the  body, 
and  that  cultures  had  survived  even  nine  transfers  to  fresh  plasma. 

Lambert  and  Hanes,^  discussing  the  growth  of  rat  and  mouse  tumors 
in  vitro,  wrote  that  the  cells  of  sarcomata  possessed  the  power  of  wan- 
dering out  separately  into  the  plasma,  probably  in  search  of  nourish- 
ment, while  those  of  carcinomata,  on  the  other  hand,  were  denied  that 
function  and  moved  outward  in  a  continuous  layer.  The  nuclei  in 
both  types  frequently  contained  division  figures,  and  the  cells  in  the 
two  cases  were  actively  phagocytic.  The  same  authors  ^  found  that 
rat  sarcoma  would  grow  in  the  plasma  of  immune  rats  quite  as  vigor- 
ously as  in  that  from  normal  or  tumor-bearing  animals,  an  observa- 
tion affording  further  proof,  they  beheved,  of  the  absence  of  specific 
cytolytic  substances  in  the  body  fluids  of  animals  immune  toward 
transplantable  tumors. 

They"*  furthermore  established  the  fact  that  rat  and  mouse  tumors 
would  grow  in  plasma  from  ahen  species,  among  which  the  order  of 

^  Jour.  American  Med.  Assoc,  1911,  Ivii,  1611. 

"^  Jour.  Exp.  Med.,  1911,  xiii,  495. 

^  Jour.  Exp.  Med.,  191 1,  xiii,  505. 

*  Froc.  Sac.  Exp.  Biol,  and  Med.,  1910-1911,  viii,  123. 


126  THE   TRANSPLANTED   TUMOR 

smtability  was :  Guinea-pig,  rabbit,  pigeon,  man,  dog,  goat  (no 
growth) . 

Those  whose  interest  prompts  them  to  inquire  more  deeply 
into  the  cultivation  of  cells  outside  the  body  should  consult  the 
papers  of  Burrows,^  Carrel,^  Carrel  and  Burrows,^  and  Lambert  and 
Hanes.^ 

Although  all  these  investigators  believed  that  they  had  observed 
cell  growth  taking  place  outside  of  the  body,  some  doubt  has  been  ex- 
pressed as  to  the  correctness  of  this  view.  Jolly  ^  did  not  think  that 
Carrel  and  Burrows  had  succeeded  in  demonstrating  the  survival  of 
cells,  and  expressed  the  view  that  certain  of  their  descriptions  were 
reminiscent  of  the  phenomena  of  necrobiosis.  And  although,  as  was 
already  known,  cellular  proliferation  appeared  to  be  possible  for  a 
time  in  certain  tissues,  between  such  a  condition  and  a  culture  with 
continuous  and  progressive  development  there  was  a  hiatus  which 
might,  perhaps,  be  conquered  at  some  future  day.  At  the  time  of  writ- 
ing, however,  the  author  considered  it  an  abuse  of  language  to  apply 
the  term  "culture"  to  the  results  so  far  obtained.  In  a  later  article 
he  ^  said  that  if  the  spread  of  cells  in  cultures  were  a  true  growth  and 
not  a  mere  dissemination,  one  should  be  able  to  hnd  evidences  of 
intense  cellular  multipHcation.  These  he  had  not  been  able  to  verify 
in  the  photographs  that  he  had  seen. 

Ewing  '^  was  of  the  opinion  that  the  cells  of  preparations  in  vitro 
were  elements  which  had  survived  and  retained  a  momentum  respon- 

^  Compt.  rend.  Soc.  Biol.,  1910,  Ixix,  291. 

Jour.  Exp.  Zoology,  1910,  x,  63. 
2  Jour.  Exp.  Med.,  1910,  xii,  460. 

Berl.  kiln.  Woch.,  191 1,  xlviii,  1364. 
^  Compt.  rend.  Soc.  Biol.,  1910,  Ixix,  293,  298,  299,  328,  332,  365,  367. 

Compt.  rend.  Soc.  Biol.,  191 1,  Ixx,  3. 

Jour.  Exp.  Med.,  191 1,  xiii,  416,  562. 

Jour.  American  Med.  Assoc,  1910,  Iv,  1379,  iSS4,  1732. 

Jour.  American  Med.  Assoc,  191 1,  Ivi,  32. 
*  Jour.  American  Med.  Assoc,  1911,  Ivi,  33,  587,  791. 

Proc  Soc.  Exp.  Biol,  and  Med.,  1910-1911,  viii,  59. 

Zeitschrift  f.  Krebsforsch.,  1911-1912,  xi,  134. 

Jour.  Exp.  Med.,  191 1,  xiv,  129,  453. 
^  Compt.  rend.  Soc.  Biol.,  1910,  Ixix,  470. 
^  Compt.  rend.  Soc.  Biol.,  1911,  Ixx,  4. 
''Zeitschrift  f.  Krebsforsch.,  1911-1912,  xi,  136. 


THE   TEANSPLANTED   TUMOR  12/ 

sible  for  certain  phenomena,  but  he  was  doubtful  whether  there  was 
any  real  physiological  growth.  Dying  cells  did  undergo  mitosis  and, 
in  fact,  this  process  seemed  to  be  increased  in  dying  tissues.  All  the 
phenomena  so  far  recorded  might  be  those  of  necrobiosis,  and  while 
the  experiments  were  of  interest,  the  growth  of  cells  outside  the  body 
had  not  yet  been  observed. 


CHAPTER  V 
RESISTANCE 

Bashford,  Murray,  and  Haaland^  have  pointed  out  that  the  term 
immunity,  so  often  used  synonymously  with  resistance,  is  an  un- 
fortunate one,  implying  as  it  does  a  diminished  liability  to  the  de- 
velopment of  spontaneous  cancer.  It  does  not  necessarily  follow  that 
animals  resistant  to  the  inoculation  of  a  tumor  are  protected  against 
the  origin  of  spontaneous  cancer,  for  Bashford,  Murray,  and  Cramer  ^ 
had  a  mouse  which,  having  been  repeatedly  inoculated  in  vain  with 
Jensen's  tumor,  nevertheless  developed  a  spontaneous  growth  of  differ- 
ent histological  type  seven  months  later.  Nor  is  this  an  isolated 
instance.  ThoreP  later  recorded  the  occurrence  of  spontaneous  tumors 
in  twelve  mice  that  had  been  inoculated  one  or  more  times  without 
success  from  ten  days  to  nine  months  previously.  The  possibility 
that  these  growths  might  have  resulted  from  a  postponed  development 
of  the  grafts  was  eliminated  by  their  location  at  a  site  far  removed 
from  that  regularly  chosen  for  implantation.  Moreover,  the  tumors 
all  occurred  in  females.  Clunet^  also  has  reported  two  spontaneous 
tumors  which  arose  in  mice  that  had  been  once  unsuccessfully  inocu- 
lated several  months  previously. 

Resistance  is  usually  divided  into  natural  and  acquired,  and  the 
latter,  in  its  turn,  into  active  and  passive. 

NATURAL   RESISTANCE 

Natural  resistance  is  said  to  be  present  in  consequence  of  age,  race, 
or  ill  health  and,  as  it  is  hardly  necessary  to  state,  in  species  other 

1  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  359. 
'^  Proc.  Roy.  Sac,  Series  B,  1907,  Ixxix,  171. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  322,  396. 
'  Verhandl.  d.  deidschen  path.  Gesellsch.,  1908,  12*'^  Tagung,  60. 
*  Recherches  exp.  stir  les  Tumeurs  malignes,  Paris,  1910,    24. 

128 


RESISTANCE  I2g 

than  that  in  which  the  tumor  arose,  or,  as  has  been  said  by  Ehrlich^  and 
others,  outside  the  hmits  of  bastardy.  It  is  known  that  sex  has  no 
influence  in  its  determination,  but  the  effects  of  pregnancy  have  not 
yet  been  so  clearly  defined. 

Influence  of  Age 

Although  when  experimental  transplantations  were  first  under- 
taken it  seemed  natural  to  suppose  that  as  cancer  originated  most 
frequently  in  old  animals  these  would  offer  the  best  soil  for  trans- 
plantation, it  was  soon  found  that  the  assumption  was  unwarranted. 
Thus  Loeb  -  noticed  that  transfer  of  a  rat  sarcoma  succeeded  in  both 
old  and  young  rats,  and  Bashford  and  Murray^  wrote :  "Age  seems 
to  have  no  influence  on  the  proportion  of  successful  transplantations, 
in  contrast  to  its  cardinal  importance  in  determining  the  initiation  of 
the  cancer-cycle."  The  case  against  the  old  animal  was  destined  to 
become  even  stronger,  for  in  the  following  year  Bashford  '^  said : 
"...  transplanted  growths  flourish  as  well,  or  better,  in  young  and 
vigorous  mice/'  and  this  yiew  had  been  consistently  expressed  since 
that  time  in  communications  from  his  laboratory.^  In  fact,  in  the 
paper  read  before  the  Royal  Society  there  were  described  inocula- 
tions into  two  series  of  mice  aged  four  and  five  days  respectively,  with 
an  issue  of  ten  tumors  in  thirteen  mice,  or  77  %  of  successful  inocula- 
tions. The  conditions  for  tumor  growth  being  thus  more  favorable  in 
young  animals  than  in  old,  Bashford  and  his  colleagues  were  led  to 
indicate  and  to  emphasize  that  there  must  be,  in  consequence,  a  differ- 
ence between  the  conditions  necessary  for  the  origin  of  a  tumor  and 
those  required  for  its  continued  growth. 

The  experiment  was  repeated  later  by  Buschke^  with  an  entirely 

1  Arh.  a.  d.  K'onigl.  Inst.f.  Exp.  Therap.,  Heft  i,  1906,  82. 

^  Jour.  Med.  Research,  1901,  N.S.,  i,  36. 

'  Sci.  Reports,  Cancer  Research  Fund,  London,  1904,  No.  i,  14. 

*  Lancet,  1905,  ii,  104. 

^  British  Med.  Jour.,  1906,  ii.  208,  1554. 

Froc.  Roy.  Soc,  Series  B,  1906,  Ixxviii,  196. 

Zeitschrift  f.  Krebsforsch.,  1907,  v,  419. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  285. 

Lancet,  1909,  ii,  700. 
^  Bcrl.  klin.  Woch.,  1911,  xlviii,  215. 


130  RESISTANCE 

confirmatory  outcome,  rats  and  mice  two,  three,  and  four  days  old 
offering  a  soil  favorable  for  the  growth  of  transplanted  cancer. 

EhrHch  and  Apolant  ^  arrived  at  similar  conclusions  and  expressed 
themselves  very  much  as  Bashiord  had  done,  namely,  that,  as  trans- 
planted cancer  grew  as  well  in  young  animals  as  in  old,  a  difference 
must  exist  between  the  conditions  necessary  for  the  inception  of  a 
tumor  and  those  requisite  for  its  growth  in  another  organism. 

Haaland  -  had  found  it  a  matter  of  daily  experience  that  young  mice 
were,  in  general,  suitable  for  tumor  implantation,  and  Lewin's  find- 
ings^ in  rats  coincided  with  the  conditions  already  defined  in  mice. 
Animals  from  five  to  eight  weeks  of  age  he  found  susceptible  in  the 
highest  degree  as  compared  ^^■ith  old  ones.  Gierke  ^  fikewise  con- 
sidered that  age  did  not  render  animals  more  suitable  for  transplan- 
tation but  that,  on  the  contrary,  young  nfice  from  eight  to  fourteen 
weeks  old  (before  puberty  had  supervened)  were  as  suitable,  and  in 
many  cases  even  more  suitable,  than  older  animals. 

The  experiments  of  Albrecht  and  Hecht^  proved  that  fully  grown 
mice  were  fairly  resistant  to  inoculation  and  that  neither  these,  nor 
very  young  animals,  were  so  well  adapted  as  half-grown  ones.  They 
finally  settled  upon  healthy  animals  over  four  weeks  of  age  as  afford- 
ing the  best  medium  for  transplantation. 

Influence  of  Race 
Beside  the  immunity  due  to  age  there  has  been  distinguished  a 
state  of  resistance  determined  by  racial  dift'erences,  fully  described 
for  the  first  time  by  Jensen.*^  In  addition  to  inoculating  his  turrior 
into  white  mice  he  tried  to  cultivate  it  in  the  common  house  mouse 
{Mus  muscidiis),  meeting,  however,  with  such  indift'erent  success  that 
in  one  series  only  one  tumor  was  obtained  in  the  ten  animals  that  had 
been  inoculated.     Once  the  growth  had  been  transferred  from  white 

1  Berl.  klin.  Woch.,  1905,  xlii,  872. 
^  Berl.  klin.  Woch.,  1907,  xliv,  718. 
^ Berl.  klin.  Woch.,  1907,  xliv,  1605. 

Zeitschrift  f.  Krebsforsch.,  1907-1908,  vi,  303. 
^  Beitr.  ziir  path.  Anat.,  etc.,  (Ziegler),  1908,  xliii,  343. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  132. 
^  Centralbl.  f.  allg.  Path.,  etc.,  1909,  xx,  1039. 

Wien.  klin.  Woch.,  1909,  xxii,  1738. 
^  Centralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1903,  xxxiv,  126. 


RESISTANCE  I3I 

mice  to  gray,  however,  its  transplantation  from  gray  to  gray  became 
easier,  and  successful  implantations  could  finally  be  performed  in 
twenty-seven  animals  out  of  eighty- four,  although  growth  was  fre- 
quently somewhat  slower  than  in  white  mice.  A  transfer  from  the 
gray  variety  back  to  white  was  rej^dily_  accomplished.  Two  attempts 
to  transmit  the  neoplasm  to  the  long-tailed  field  mouse  {Mus  syhati- 
cus)  were  unsuccessful,  nor  was  the  tumor  transplantable  into  other 
varieties  of  white  mice.  The  same  author,^  in  a  later  description  of 
two  propagable  sarcomata  of  the  tame  rat,  said  that  they  would  not 
grow  at  all  in  wild  juts  and  could  be  inoculated  only  occasionally  into 
variegated  rats  from  Hamburg,  Berlin,  and  London.  On  the  contrary 
in  white  and  variegated  rats  of  the  laboratory  strain  and  in  Copen- 
hagen rats  (undoubtedly  closely  related  to  the  laboratory  stock)  they 
could  be  grown  very  successfully,  the  tumor  from  one  rat  yielding 
87.5  %  of  daughter  tumors  and  that  from  the  second  57.7  %.  The 
transplantation  of  both  tumors  being  continued,  there  occurred  during 
cultivation  such  an  increase  in  the  percentage  of  successful  results 
that  in  the  fourth,  fifth,  and  sixth  generations  the  yield  with  the  tumor 
from  the  first  rat  had  risen  to  100  %  and  with  that  from  the  second 
to  85  %,  both  calculated  in  Danish  rats.  This  rise  was  also  evident, 
however,  in  foreign  rats,  for  when  the  first  tumor  in  its  fifth  genera- 
tion was  inoculated  from  a  Danish  rat  into  five  Berlin,  three  Hamburg, 
and  ten  London  rats,  four,  two,  and  seven,  respectively,  of  these  rats, 
eleven  -  in  all,  or  61. i  %,  developed  tumors,  while  in  the  first  three  gen- 
erations tumors  had  followed  in  only  10.5  %  of  the  animals  inoculated. 
The  question  of  the  effect  of  race  upon  the  suitability  of  the  soil 
occurred  also  to  Loeb,^  but  he  left  its  final  solution  to  be  determined 
by  future  investigations.  In  a  later  article  he  *  described  the  success- 
ful transfer  of  a  sarcoma  of  the  white  rat  to  a  cross  between  the  gray 
and  the  white  rat,  and  the  failure  to  transplant  a  tumor  of  the  Japanese 
waltzing  mouse  to  ordinary  white  mice. 

^  Zeitschrift.  f.  Krebsforsch.;  1908-1909,  vii,  49. 

^  There  is  a  discrepancy  in  the  numbers  here :  11  should  read  13  and  the  successful  re- 
sults would,  therefore,  number  72.2  %.  Professor  Jensen  was  kind  enough  to  reply  to  a 
letter  of  inquiry  on  this  point,  that  5  Berlin,  5  Hamburg,  and  10  London  rats  were  inocu- 
lated, and  that  of  these  20  animals,  14,  or  70  %,  developed  tumors.  Growth  had,  however, 
been  so  slow,  that  when  his  paper  was  published  the  results  had  not  been  final. 

^  Jour.  Med.  Research,  1901,  N.S.,  i,  36.  *  American  Medicine,  1905,  x,  265. 


132  RESISTANCE 

Bashford  and  Murray/  having  received  Jensen's  tumor  with  the 
information  that  in  Denmark  it  had  grown  best  in  white  mice,  tested 
its  growth  in  Enghsh  white  mice,  which  they  found  yielded  less  favor- 
able results  than  other  races  of  tame  Enghsh  mice,  as  yellow,  black 
and  white,  yellow  and  white,  and  black ;  in  what  were  known  as  "blue 
mice"  they  had  not  been  able  to  get  the  tumor  to  grow  at  all.  Bash- 
ford,^  with  Murray  and  Cramer,^  recording  later  and  more  elaborate 
experiments,  described  attempts  to  transplant  spontaneous  or  propa- 
gable  tumors  of  Danish,  French,  and  German  mice  into  Enghsh  breeds. 
The  results,  which  were  entirely  analogous  to  those  first  obtained, 
demonstrated  that  the  transfer  of  mahgnant  new  growths  to  mice 
of  slightly  different  race  might  present  considerable  difficulties.  The 
apparent  unsuitabihty  of  blue  mice  for  Jensen's  tumor,  as  pubHshed 
in  the  earher  cornmunication,  proved,  however,  not  to  be  absolute, 
and  in  later  experiments  this  breed  developed  growths  which  in  several 
cases  attained  a  huge  size.  The  same  phenomenon  became  apparent 
in  other  strains  of  Enghsh  mice  as  concerned  the  inoculation  both  of 
Jensen's  tumor  and  one  of  German  origin,  and  the  percentage  of  suc- 
cessful inoculations  increased  gradually  to  a  point  where  the  results 
eventually  equaled,  or  promised  to  equal,  those  obtained  in  Danish 
and  German  mice.  After  Jensen's  tumor  had  been  growing  in  Enghsh 
mice  for  three  years  it  was  inoculated  back  into  Danish  mice  by 
Bashford,  Murray,  Haaland,  and  Bowen,^  who  recorded  that  its  power 
to  grow  in  the  original  soil  had  not  been  lost. 

According  to  Michaelis,^  mice  sent  him  from  Denmark  provided 
a  better  soil  for  the  growth  of  Jensen's  carcinoma  than  mice  obtained 
in  Berhn ;  and  Clowes  ^  found  difficulty  at  first  in  transplanting  Jen- 
sen's tumor  into  gray  mice  of  American  stock. 

Hertwig  and  Poll  ^  did  not  believe  that  racial  resistance  actually 
deserved  the  importance  that  had  been  ascribed  to  it.  The  white 
mouse,  they  wrote,  has  been  for  years  an  article  of  commerce,  and 

1  Sci.  Reports,  Cancer  Research  Fund,  London,  1904,  No.  i,  13. 
^Lancet,  1905,  ii,  1673. 

^  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  22. 
*  Third.  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  273. 
^  Verhandl.  d.  Komitees  f.  Krebsforsch.,  1903-1904,  iii,  38.     See  Deut.  med.  Woch.,  1904, 
XXX,  1264. 

^  Johns  Hopkins  Hasp.  Bull.,  1905,  xvi,  130. 

''  Abhandl.  d.  Kiinigl.  Preuss.  Akad.  der  Wissensch.,  1907,  11. 


RESISTANCE  I33 

from  Berlin,  for  example,  fifty  to  sixty  thousand  were  exported  yearly 
by  dealers  who  collected  them  from  various  small  breeding  estabhsh- 
ments.  Some  years  ago,  in  fact,  many  of  the  so-called  "Berlin"  mice 
had  been  imported  from  Italy.  Thus  the  investigator  could  never 
be  sure  of  the  origin  of  his  stock,  and  it  might  very  well  be  that  what 
had  been  described  by  this  or  that  worker  as  Copenhagen  or  Frank- 
fort mice  were  descended,  directly  or  indirectly,  from  Berlin  mice. 
On  a  subsequent  page  ^  the  authors  summed  up  their  experience  with 
three  tumors  that  had  been  transplanted  from  white  to  gray  mice  and 
conversely.  The  results  were,  in  the  main,  so  favorable  that  the 
authors  felt  justified  in  opposing  the  view  that  mouse  cancer  was 
transferable  only  between  very  closely  related  individuals,  and  that 
differences  in  breed  or  in  diet  constituted  an  obstacle  against  success- 
ful inoculation. 

Haaland  ^  found  difficulty  in  getting  Jensen's  mouse  tumor  to  grow 
in  French  and  Russian  mice,  and  ^  in  transferring  Ehrlich's  mouse  sar- 
coma to  Norwegian  mice  —  so  much  difficulty,  in  the  latter  case,  that 
he  was  barely  able  to  keep  the  tumor  alive.  When,  a  few  months 
later,  he  was  again  in  a  position  to  inoculate  the  latter  growth  into  the 
strain  of  mice  used  in  Ehrlicli's.  laboratory,  he  was  surprised  to  see 
that  it  flourished  with  its  original  vigor.  A  Berlin  stock  was  sus- 
ceptible to  this  tumor,  while  '■one  from  Hamburg  was  much  less  so, 
and  in  the  latter  case  the  tumor  had  not  been  able  to  adapt  itself  even 
after  five  passages.  Eighteen  mice  of  Danish  origin  inoculated  with 
this  sarcoma  did  not  produce  a  permanent  tumor  in  one  single  instance, 
but  a  strain  of  mice  that  had  probably  originated  in  Germany,  although 
it  had  been  several  years  in  Norway,  was  fairly  susceptible.  Now 
it  might  be  imagined,  said  Haaland,  that  the  susceptibility  of  certain 
breeds  depended  upon  general  conditions  or,  in  other  words,  that  in 
such  strains  cell  transplantation  would  always  be  more  successful. 
Were  this  true,  one  would  expect  these  strains  to  be  susceptible  to 
other  tumors  as  well.  But  that  the  case  was  not  so  simple  Haaland 
showed  by  inoculating  a  mixture  of  Ehrlich's  sarcoma  and  Jensen's 
carcinoma.     In  Berlin  mice  the  sarcomatous  element  of  the  mixture 

1  Abhandl.  d.  Konigl.  Preuss.  Akad.  der  Wissensck.,  1907,  54. 
^  Ann.  de  Vlnst.  Past.,  1905,  xix,  187. 
^  Bcii.  kliii.  Woch.,  1907,  xliv,  714. 


134  RESISTANCE 

was  alone  able  to  proliferate,  while  in  Danish  mice,  on  the  contrary, 
the  one  tumor  that  did  grow  was  a  pure  Jensen  carcinoma.  Thus  it 
was  clear  that  there  were  involved,  instead  of  a  general  condition 
where  certain  breeds  of  mice  were  susceptible  to  all  growths,  special 
and  very  specific  factors  which  behaved  differently  toward  different 
tumors.  The  Copenhagen  mice  were  at  once  susceptible  to  Jensen's 
carcinoma  and  resistant  to  Ehrlich's  sarcoma,  while  conversely,  those 
from  BerHn  were  highly  susceptible  to  the  sarcoma  and  yet  resistant 
toward  the  carcinoma. 

When  Haaland  left  Frankfort  he  took  some  of  the  laboratory  strain 
of  mice  to  Norway,  and  three  months  later  inoculated  six  of  them  with  ' 
sarcoma  fresh  from  EhrHch's  institute.  To  this  growth,  however,  they 
proved  themselves  highly  resistant,  although  previously  mice  of  the 
same  stock  had  been  susceptible;  furthermore,  their  descendants 
were  also  resistant  to  the  tumor.  The  only  possible  explanation  was 
that  residence  in  Norway  had  made  the  Frankfort  mice  an  unfavor- 
able medium,  probably  because  they  had  received  there  a  diet  different 
from  that  to  which  they  were  accustomed  in  Germany. 

Jensen  ^  also  could  see  no  other  solution,  and  suggested  that  the 
condition  was  of  practical  as  well  as  of  theoretical  interest  because  of 
the  chance  of  influ^ncingjnetastasis  and  recurrence  in  human  beings. 
One  could  with  perfect  justice  compare  tumors  obtained  by  inocula- 
tion with  those  arising  by  metastasis,  and  if  it  should  be  proved  that 
a  radical  change  of  diet  was  capable  of  affecting  the  susceptibiHty  of 
the  mouse  to  transplantable  tumors,  the  possibility  could  not  be  ex- 
cluded that  some  influence  upon  metastasis  and  recurrence  might  be 
achieved  in  man  by  the  same  process. 

Gierke  ^  did  not  believe  that  the  conclusion  of  Hertwig  and  Poll 
could  be  extended  to  include  all  mouse  tumors,  for  although  there 
might  be  some  which  were  insensitive  to  finer  differences  among 
mice,  the  authors  had  not  proved  that  this  was  so  of  all 
growths.  Gierke  transplanted  three  EngHsh  tumors  into  both 
Enghsh  and  German  mice,  with  the  result  that  the  percentage  of 
success  was  much  higher  in  the  former — 38,  57,  and  75%,  as  com- 
pared with  9,  14,  and  21%  in  the  German  animals.  The  rate  of 
growth  in   English  mice  was  considerably  faster,  also,  than  in  the 

^  Zeitschrift  f.  Krebsforsch.,  1908-1909,  vii,  283. 
^  Zeitschrift  f .  Krebsforsch.,  1908-1909,  vii,  331. 


RESISTANCE  I35 

others.  When,  however,  there  was  inoculated  into  English  and  German 
mice  a  strain  of  the  Jensen  tumor  that  had  been  growing  for  years 
in  English  breeds,  no  disparity  was  found  either  in  the  percentage  of 
takes  or  in  the  rate  of  growth.  These  differences  in  suitability  for 
inoculation  Gierke  was  inclined  to  ascribe  rather  to  food  and  surround- 
ings than  to  actual  racial  pecuHarities,  for  the  reason  that  they  had 
been  most  marked  between  the  stocks  of  different  countries  and  usu- 
ally lacking  among  those  native  to  the  same  country.  Experiments 
not  controlled  by  simultaneous  inoculation  into  native  animals  were 
always  open  to  the  criticism  that  an  unfavorable  result  might  have 
occurred  because  the  tumor  happened  at  the  time  to  be  in  the  negative 
phase  of  growth  described  by  Bashford  and  Murray. 

Lewin/  on  the  contrary,  expressed  his  entire  agreement  with  Hert- 
wig  and  Poll,  basing  his  statement  upon  experiments  conducted  in 
both  rats  and  mice.  His  rat  tumor  grew  in  white,  variegated,  and  black 
rats  from  many  different  localities,  and  he  was  able  to  transplant 
Jensen's  rat  sarcoma  into  animals  from  Berlin  and  Diisseldorf  while, 
furthermore,  a  gray  mouse  tumor  had  been  inoculated  with  success 
•into  white  mice  and  vice  versa. 

In  the  experiments  of  Stahr  ^  there  were  differences  in  susceptibility 
between  Diisseldorf  mice  and  those  from  BerKn.  The  Diisseldorf 
mice,  representing  the  excess  stock  of  an  animal  fancier,  had  been  kept 
for  more  than  half  a  year  in  large  airy  cages  and  had  been  fed  on  hemp 
seed  and  milk,  but  since  their  arrival  at  the  laboratory  they  had  been 
given  bread  soaked  in  water,  food  which  the  laboratory  strain  of 
Berhn  mice  (obtained  through  an  ordinary  dealer)  had  regularly  re- 
ceived. Two  tumor  strains  were  employed  —  one  from  Berlin  and 
one  from  Nuremberg. 

The  Berlin  tumor  grew  better  at  first  in  the  Berhn  mice  of  the  labora- 
tory strain  than  it  did  in  those  from  Diisseldorf,  which  had  just 
entered  the  laboratory.  But  after  the  latter  strain  had  been  for  some 
months  on  the  same  diet  and  in  the  same  surroundings  as  the  Berhn 
stock  they  proved  quite_a^_sensitive  to  the  Berhn  tumor,  or  perhaps 
even  more  susceptible. 

1  Berl.  klin.  Woch.,  1907,  xliv,  1605. 
Zeitschrift  f.  Krebsforsch.,  1907-1908,  vi,  302. 

2  Centralbl.  f.  allg.  Path.,  etc.,  1909,  xx,  628. 


136  RESISTANCE 

The  Nuremberg  tumor  was  inoculated  into  Berlin  mice  accustomed 
to  the  laboratory  food  and  surroundings,  as  well  as  into  a  fresh  supply 
of  Diisseldorf  mice  from  the  fancier  previously  mentioned.  In  each  of 
the  two  experiments  undertaken,  the  newly  introduced  mice  were  less 
suitable  than  those  of  the  laboratory  strain.  The  author  concluded, 
although  advising  caution  on  account  of  the  small  figures  at  his  com- 
mand^ that  the  Diisseldorf  mice  reacted  differently  toward  tumor  in- 
oculation because  they  had  been  kept  on  a  diet  different  from  that  of 
the  laboratory  strain,  and  because  their  health  had  been  impaired  by 
the  much  less  favorable  hygienic  conditions  in  the  laboratory. 

Cuenot  and  Mercier  ^  found,  between  Parisian  mice  and  those  of" 
Nancy,  as  concerned  their  susceptibility  toward  Borrel's  tumor  "B," 
a  disparity  which,  exhibiting  itself  in  a  smaller  yield  and  a  slower 
growth,  rapidly  disappeared.  The  authors,  having  inoculated  many 
mice  of  various  colors  without  finding  any  relation  between  race  and  re- 
sistance, concluded  that  immunity  must  rest  upon  invisible  differences. 

Uhlenhuth  and  Weidanz,^  in  an  inquiry  regarding  the  importance  of 
racial  differences,  determined  that  Enghsh  mice  were  more  suitable  for 
the  inoculation  of  an  English  tumor  than  Berlin  mice,  for  not  only  was 
there  a  lower  percentage  of  takes  in  the  latter,  but  spontaneous  cure 
occurred  more  frequently. 

Albrecht  and  Hecht^  had  difficulty  in  inoculating  spontaneous 
carcinomata  from  mice  of  other  countries  into  Vienna  mice.  Five 
foreign  tumors  were  ingrafted  unsuccessfully  or  with  difficulty,  only 
two  such  strains  being  readily  transmissible. 

Tyzzer  '^  noted  a  difference  in  the  susceptibility  of  certain  races  of 
mice  to  the  Jensen  tumor  and,  furthermore,^  that  ordinary  tame  mice 
were  quite  insensitive  to  a  growth  originating  in  a  Japanese  waltzing 
mouse.  Japanese  waltzing  mice,  in  their  turn,  were  less  suitable  than 
ordinary  breeds  for  the  inoculable  tumors  of  the  latter. 

Gay  ^  observed  throughout  his  experiments  an  important  variation 

-  Compt.  rend,  de  I'Acad.  des  Sc,  1908,  cxlvii,  1003. 
^  Arb.  a.  d.  Kaiserl.  Gesundheiisamte,  1909,  xxx,  438. 
'  Centralbl.  f.  allg.  Path.,  etc.,  1909,  xx,  1039. 

Wien.  klin.  Wock,  1909,  xxii,  1738. 
*  Jour.  Med.  Research,  1907-1908,  N.S.,  xii,  146. 
^  Jour.  Med.  Research,  1909,  N.S.,  xvi,  519. 
^  Boston  Med.  and  Surg.  Jour.,  1909,  dxi,  210. 

Proc.  Soc.  Exp.  Biol,  and  Med.,  1908-1909,  vi,  74. 


RESISTANCE 


137 


in  racial  sensitiveness  to  the  Flexner  rat  tumor,  for  whereas  100% 
of  the  most  susceptible  strain  were  inoculable,  only  50  %  of  the  rats 
from  a  second  dealer  could  be  successfully  ingrafted,  while  among 
those  from  still  another  source  the  yield  was  even  smaller. 

Influence  of  Health 

Mice  in  poor  condition  do  not  offer  so  favorable  a  soil  for  tumor 
growth  as  do  healthy  ones,  according  to  Bashford^  and  Haaland.^ 
This  may  serve  to  explain  the  results  of  those  who  have  described  the 
attainment  of  resistance  by  treatment  with  autolyzed  tissues,  since 
the  possibility  of  sepsis  in  the  animals  of  such  experiments  has  not 
been  eliminated. 

Influence  of  Sex 

No  observer  has  yet  discovered  any  difference  in  susceptibility 
between  males  and  females  —  at  least  this  has  been  the  experience 
of  Loeb,^  Ehrlich,*  Gierke,^  Lewin,^  and  many  others. 

Influence  of  Pregnancy 

It  has  been  asserted  and  denied  that  the  existence  of  pregnancy  ren- 
dered animals  less  susceptible  to  implantation ;  and  although  Morau '' 
and  Herzog  ^  had  written  that  gestation  accelerated  the  evolution  of 
tumors,  and  Bashford  and  Murray^  that  "Pregnancy  and  full  sexual 
activity  in  the  male  (as  determined  by  microscopical  examination  of 
the  testes)  constitute  no  bar  to  successful  transplantation,"  Haaland,^" 
on  the  contrary,  had  found  that  pregnancy  often  exerted  an  inhibitory 
influence  upon  the  prohferation  of  tumors,  the  effect  of  which  was  to 
produce  a  striking  retardation  of  their  growth  in  pregnant  animals  as 
compared  with  animals  not  bearing  young.     Uhlenhuth  and  Weidanz  ^^ 

1  British  Med.  Jour.,  1907,  ii,  28. 

Lancet,  1907,  ii,  32. 
^  Berl.  klin.  Woch.,  1907,  xliv,  718. 
^  Jour.  Med.  Research,  1901,  N.S.,  i,  36. 
*  Arb.  a.  d.  Konigl.  Inst.f.  Exp.  Therap.,  1906,  Heft  i,  81. 
^  Beitr.  zur  path.  4-nat.,  etc.,  (Ziegler),  1908,  xliii,  343. 

Third  Set.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  132. 
°  Zeitschrift  f.  Krebsforsch.,  1907-1908,  vi,  304. 
''Arch,  de  Med.  exp.  et  d'Anat.  path.,  1894,  vi,  693. 
^Jour.  Med.  Research,  1902,  N.S.,  iii,  76. 

^  Sci.  Reports,  Cancer  Research  Fund,  London,  1904,  No.  i,  14. 
^°  Berl.  klin.  Woch.,  1907,  xliv,  718. 
^^  Arb.  a.  d.  Kaiserl.  Gesundheitsamte,  1909,  xxx,  440. 


138  RESISTANCE 

had  also  observed  this  retardation  and,  furthermore,  that  spontaneous 
regression  occurred  oftener  in  pregnant  mice. 

Bridre  ^  chose  males  for  inoculation  whenever  it  was  possible  be- 
cause of  the  low  percentage  of  positive  inoculations  occurring  in  preg- 
nant females,  while  Ehrlich  ^  had  noticed  repeatedly  that  inoculation 
into  animals  bearing  young  was  followed  with  extraordinary  frequency 
by  negative  results,  or  was  at  least  attended  by  the  development  of 
tumors  in  which  growth  was  greatly  retarded. 

Pregnancy,  according  to  Albrecht  and  Hecht,^  whether  already 
present  at  the  time  of  inoculation,  or  commencing  afterward,  influenced 
the  estabhshment  of  a  tumor  or  its  subsequent  growth  just  as  little 
as  the  presence  of  a  tumor  influenced  conception  or  pregnancy. 

Cuenot  and  Mercier^  reported  that  Borrel's  tumor  "B"  (which 
rarely  underwent  spontaneous  absorption),  if  inoculated  before  fecun- 
dation, would  develop  throughout  gestation  and  recede  during  lacta- 
tion. But  if  one  mouse  only  were  born  and  the  activity  of  the  mam- 
mary gland  were  in  consequence  at  a  minimum,  the  tumor  did  not 
regress,  nor  did  absorption  take  place,  even  in  the  presence  of  several 
young,  if  a  tumor  were  so  situated  that  its  vascularization  was  inde- 
pendent of  that  of  the  mammary  gland. 

Fichera  ^  explained  the  inconsistencies  that  had  been  observed  in  the 
relations  between  pregnancy  and  tumor  growth  by  assuming  that 
when  many  embryos  were  present  the  specific  food-stuffs  were  almost 
wholly  demanded  by  them,  while  if  there  were  but  few  the  nutrient 
material  was  available  for  the  tumor  cells  as  well. 

ACQUIRED   RESISTANCE,    ACTIVE    AND   PASSIVE 

Active  Resistance  evolved  by  Tumor 

It  was  reported  first  by  Clowes,^  and  later  by  Gaylord,  Clowes,  and 
Baeslack,^  that  the  Jensen  carcinoma  sometimes  underwent  spontane- 

^  Ann.  de  VInst.  Past.,  1907,  xxi,  763. 

^  Verhandl.  d.  deidschen  path.  Gesellsch.,  1908,  12'^  Tagung,  29. 

^Wien.  klin.  Woch.,  1909,  xxii,  1738. 

*  Compt.  re)id.  de  I'Acad.  des  Sc,  1909,  cxlix,  1012. 

^  Cited  by  Apolant,  Jour.  Exp.  Med.,  1911,  xiv,  320. 

^  Johns  Hopkins  Hasp.  Bull.,  1905,  xvi,  130. 

^  Med.  News,  1905,  Ixxxvi,  91. 


RESISTANCE  I39 

ous  regression,  and  this  phenomenon  was  later  described  in  detail  by 
Gaylord  and  Clowes.^  Clowes  and  Baeslack  ^  then  found  that  animals 
in  which  a  cure  had  taken  place  were  refractory  toj^-inoculation,  since 
among  thirty  mice  in  which  the  Jensen  carcinoma  had  been  absorbed 
not  one  developed  a  tumor  upon  re-inoculation  with  the  same  growth, 
although  ten  of  the  group  were  subjected  to  a  third  implantation. 

Flexner  and  Jobling  ^  noted  that  among  seventy  rats  which  had  been 
able  to  rid  themselves  of  the  Flexner- Jobling  adeno- carcinoma,  only 
17  %  developed  growths  upon  re-inoculation  with  that  tumor,  and 
Lewin  ^  reported  that  he  had  seen  such  resistance  frequently  after  the 
absor^iorijofjiisjywn  rat  carcinoma. 

As  a  corollary  to  these  observations  there  arose  the  question  whether 
a  mouse  once  ingrafted  without  result  could  be  successfully  inoculated 
at  a  subsequent  trial.  Although  Jensen '"  had  observed  that  in  about 
half  his  mice  the  graft  failed  to  grow  and  that  such  animals  were  then 
resistant,  Bashford,  Murray,  and  Cramer  ^  were  of  the  opinion  that 
inoculation  of  mice  in  which  an  implantation  had  been  fruitless 
succeeded  in  nearly  the  same  percentage  as  in  the  first  instance. 
A  year  later  Bashford '''  reiterated  this  statement,  but  qualified 
it  with  the  remark  that  if  the  process  were  repeated,  negative 
mice  being  discarded  each  time,  animals  could  be  ultimately 
obtained  with  a  more  pronounced  power  of  resistance,  affording, 
for  example,  12%  of  tumors  as  compared  with  68%  among  controls 
of  the  same  age.  A  similar  result  had  been  substantiated  for  mice 
unsuccessfully  injected  with  two  spontaneous  sarcomata  and  various 
spontaneous  carcinomata,  when  the  animals  were  afterward  inoculated 
with  Jensen's  tumor.  After  further  investigation  he  was  able  to  con- 
firm even  more  fully  the  results  of  others,  and  in  a  paper  written  in 
conjunction  with  Murray  and  Cramer  ®  said  that  differences  in  the  size 

1  Surgery,  Gynecology,  and  Obstetrics,  1906,  ii,  633. 

^  Med.  News,  1905,  Lxxxvii,  969. 

^  Proc.  Soc.  Exp.  Biol,  a/td  Med.,  1907-1908,  v,  17. 

*  Zeitschrift  f.  Krehsforsch.,  1907-1908,  vi,  306. 

*  Centralbl.f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1903,  xxxiv,  126. 

^  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  51. 
^  British  Med.  Jour.,  1906,  ii,  209. 

*  Proc.  Roy.  Soc,  Series  B,  1907,  Ixxix,  179. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  331. 


140  RESISTANCE 

of  dose  would  probably  explain  the  apparent  contradictions  between 
his  own  earlier  work  and  that  of  other  observers.  In  later  experi- 
ments the  mass  of  tumor  absorbed  in  the  course  of  three  or  four  nega- 
tive inoculations  with  0.05  gram  had  been  so  great  that  the  animals 
could  not  be  regarded  as  comparable  with  those  in  earlier  experiments, 
which  had  received  relatively  insignificant  doses  (o.oi  to  0.02  gram). 

In  this  connection  the  experiments  of  Bridre  ^  are  of  importance. 
Unable  at  first  to  discover  evidences  of  resistance  in  unsuccessfully  in- 
oculated mice,  he  conceived  the  idea  that  his  failure  might  have  been 
due  to  the  employment  of  an  insufficient  primary  dose.  Accordingly, 
he  inoculated  tumor_emulsion  in  amounts_fi.ve  or  six  times  asjarge  as 
the  fragment  that  had  been  used  in  his  earher  experiments  and  ob- 
tained an  immunity  so  perfect  that  no  tumors  developed  in  the  treated 
animals,  although  the  controls  yielded  55  %. 

Michaelis,  Fleischmann,  and  Pincussohn  ^  had  positive  results  in 
about  60%  of  normal  mice,  while  in  those  which  had  proved  refrac- 
tory to  a  first  attempt  nodules  developed  after  re-implantation  in  only 
12  %.  It  happened  occasionally  that  a  mouse  inoculated  three 
times  in  vain  could  be  successfully  ingrafted  at  a  fourth  attempt. 

Borrel  ^  noted  that  while  55  %  of  mice  contracted  a  tumor  after 
a  first  implantation,  only  12  to  15  %  of  the  negatives  developed  them 
after  the  second,  and  none  after  the  third. 

Ehrlich  ^  found  that  in  mice  unsuccessfully  inoculated  with  a 
hemorrhagic  growth  giving  but  a  small  percentage  of  daughter  tumors, 
subsequent  inoculation,  even  with  a  more  vigorous  strain,  produced 
but  few  tumors.  Furthermore,  the  refractory  condition  was  still 
more  distinct  in  those  mice  which  had  been  able  to  resist  a  neoplasm 
that  would  grow  in  a  large  percentage  of  the  mice  inoculated. 

Flexner  and  Jobhng  ''  reported  two  hundred  and  one  rats  unsuc- 
cessfully inoculated  with  their  adeno-carcinoma  while  its  virulence  was 
below  the  maximum,  49  %  of  which  developed  tumors  upon  re-im- 
plantation with  the  virulent  tumor. 

'  Ann.  de  I'lnst.  Past.,  1907,  xxi,  764.  ^  Deut.  med.  Woch.,  1907,  xxxiii,  827. 

^  Bull,  de  VInst.  Past.,  1907,  v,  603. 

^  Arh.  a.  d.  Konigl.  Inst.f.  Exp.  Therap.,  1906,  Heft  i,  90. 

Zeitschrift  f.  aerztUche  Fortbildimg,  1906,  iii,  211. 

Zeitschrift  f.  Krebsforsch.,  1907,  v,  73. 
'  Proc.  Soc.  Exp.  Biol,  and  Med.,  1907-1908.  v,  17. 


RESISTA^XE  141 

Clowes  and  Baeslack  ^  stated  that  in  a  series  where  the  mice  were 
intentionally  treated  with  a  strain  so  weak  as  to  afford  but  about 
50  %  of  abortive  tumors,  the  animals  in  which  the  attempt  had  been 
fruitless  all  developed  fair-sized  growths  upon  re-inoculation  with 
a  more  \dgorous  strain.  And  later,  Clowes  -  himself  recorded  the 
outcome  following  re-inoculation  of  mice  refractory  to  the  Jensen 
tumor.  From  30  to  35  %  of  growths  were  obtained  after  the  pri- 
mary inoculation  ;  the  first  re-inoculation  gave  10  %,  and  the  second  nil. 
The  re-inoculation  of  the  sur\-ivors  of  less  vigorous  tumor  strains  with 
one  of  more  active  growth  did  not  indicate,  especially  when  large 
doses  were  employed,  that  there  had  been  conferred  as  high  a  de- 
gree of  resistance  as  Ehrlich  had  described,  although  the  difference 
might  be  due  to  diversities  in  the  methods  of  transplantation  employed, 

Hertwig  and  Poll  ^  thought  that  mice  were  not  made  refractory  by 
an  unsuccessful  inoculation  and  expressed  the  behef  that  in  such  cases 
there  was  involved  merely  the  artificial  selection  of  animals  naturally 
immune,  as  had  already  been  suggested  by  Jensen  ^  and  by  MichaeHs.^ 

Pan-immunity :  —  Not  a  Httle  attention  has  been  devoted  to 
attempting  a  definition  of  the  Kmits  within  which  immunity  produced 
by  the  absorption  of  tumors  is  specific. 

EhrHch  ^  believed  that,  in  general,  a  preliminary  unsuccessful 
inoculation  with  carcinoma  protected  not  alone  against  all  strains  of 
carcinoma  but  equally  against  all  sarcomata,  and  conversely,  that 
preHminary  inoculation  with  sarcoma  would  protect  not  only  against 
all  sarcomata  but  against  all  carcinomata  as  well.  So  far  as  chon- 
droma was  concerned  he  was  of  the  impression,  derived  from  a  series 
of  experiments  at  that  time,  however,  still  unfinished,  that  in  some 
animals  which  were  resistant  to  sarcoma  or  carcinoma  the  chon- 
droma grew  more  slowly  than  usual  or,  perhaps,  not  at  all.  Still,  any 
considerable  resistance  to  the  chondroma  was  achieved  apparently 
only  after  the  sarcoma-carcinoma  resistance  had  jjeen  raised   to   a 

1  Med.  News,  1905,  IxxxN^ii,  969.  ^  British  Med.  Jour.,  1906,  ii,  1551. 

^  Ahhandl.  d.  Konigl.  Preiiss.  Akad.  d.  Wissensch.,  1907,  26. 

^Centralbl.  f.  Bakl.,  etc.,  erste  Abt.,  Orig.,  1903,  xxxiv,  126. 

^  Zeitschrift  f .  Krebsforsch.,  1907,  v,  191. 

^  Zeitschrift  f.  aerzlliche  Fortbildung,  1906,  iii,  211. 

Arh.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  92. 

Zeitschrift  f.  Krebsforsch.,  1907,  v,  74. 


142  RESISTANCE 

maximum.  Hence,  as  this  condition  of  artificially  induced  resistance 
was,  to  a  certain  extent  at  least,  not  a  narrow  one,  Ehrlich  saw  no 
objection  to  postulating  a  state  of  pluri-immunity  or  even  pan- 
immunity. 

It  had  been  previously  recorded  by  Bashford  ^  that  mice  which  had 
rid  themselves  of  a  certain  transplantable  mammary  carcinoma  were 
more  resistant  to  re-inoculation  with  this  tumor  than  with  Jensen's  car- 
cinoma. There  was,  therefore,^  "...  a  degree  of  protection  which 
is  common,  and  a  certain  degree  which  is  specific."  But  the  common 
protection  was,  as  Bashford,  Murray,  and  Cramer  ^  indicated,  con- 
ferred by  the  tumor  not  as  tumor,  but  as  mouse  tissue,  and  Bashford, ' 
Murray,  and  Haaland  ^  could  discover  no  evidence  that  carcinoma 
evolved  more  resistance  to  sarcoma  than  did  normal  tissue,  although 
sarcoma  protected  to  a  high  degree  against  carcinoma.  They  could 
not,  therefore,  subscribe  to  EhrHch's  behef  that  protection  between 
carcinoma  and  sarcoma  was  mutual  and  of  equal  degree. 

Haaland,^  in  earHer  experiments,  had  seen  that  an  unsuccessful 
inoculation  with  Jensen's  tumor  did  not  protect  against  the  subsequent 
implantation  of  sarcoma,  but  Lewin,^  on  the  contrary,  was  convinced 
that  there  could  exist  in  the  rat  conditions  of  resistance  common  to 
sarcoma  and  carcinoma.  Rats  unsuccessfully  inoculated  with  sarcoma, 
or  in  which  a  carcinoma  had  undergone  spontaneous  absorption,  had 
been,  in  his  experience,  refractory  to  both  carcinoma  and  sarcoma. 

Michaelis,  Fleischmann,  and  Pincussohn  ^  found  that  mice  unsuc- 
cessfully inoculated  with  Jensen's  tumor  were  not  resistant  to  a  BerUn 
growth,  and  Gierke,^  that  mice  negative  to  the  inoculation  of  a  tumor 
were  protected  in  an  extraordinarily  high  degree  against  the  same,  and 
to  a  somewhat  lower  degree  against  different  tumors. 

1  British  Med.  Jour.,  1906,  ii,  209. 
Lancet,  1906,  ii,  314. 

2  Science  Progress,  1907,  ii,  20. 

^  Proc.  Roy.  Soc,  Series  B,  1907,  Ixxix,  179. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  332. 
*  Jour.  Path,  and  Bact.,  1908,  xii,  436.  ^  Berl.  kiln.  Woch.,  1907,  xliv,  716. 

^  Berl.  klin.  Woch.,  1907,  xliv,  1606. 

Zeitschrift  f.  Krebsforsch.,  1907-1908,  vi,  309. 
''  Deut.  med.  Woch.,  1907,  xxxiii,  827. 
^  Beitr.  znr  path.  Anat.,  etc.,  (Ziegler),  1908,  xliii,  346. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  135. 


1-12. 

CONTROL. 
NORMAL  RATS. 

Average  weight.  53  g-rms. 


14  21 

28  6 

11 

18  25 

k 

1 

' 

» 

f 

f 

ft 

1 

2 

• 

t 

f 

^ 

f 

• 

3 

\ 

1 

f 

• 

4 

• 

f 

f 

5 

' 

• 

6 

• 

\ 

< 

f 

• 

« 

7 

i 

1 

1 

# 

8 

' 

• 

- 

- 

- 

- 

9 

• 

■ 

- 

- 

- 

- 

10 

- 

- 

- 

- 

- 

- 

11 

* 

• 

12 

• 

ia-24. 

0-1  c.c.  MOUSE  SARC0JL4. 

13.11.07. 

Average  weight.  44  grms. 


'^ 

21 
<2 

28 

^ 

fV 

18 

25 

1 

13 

• 
• 

f 

f 

t 

f 

14 

< 

• 

• 

# 

• 

15 

• 

f 

• 

f 

f 

16 

• 

• 

« 

t 

t 

17 

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t 

18 

t 

f 

t 

19 

t 

20 

' 

21 

- 

- 

- 

- 

- 

22 

- 

- 

- 

- 

- 

23 

24 

- 

- 

25-35. 
01  c.c.  CAT  SARCOMA. 

18.xi.07 
Average  weight  42  grmt. 


14 

12 

21 
-12 

28 
12 

^ 

11 

18 

25 

I 

25 

1 

• 

t 

• 

f 

t 

26 

% 

• 

« 

• 

# 

i 

f 

27 

• 

• 

f 

• 

« 

• 

• 

f 

28 

« 

« 

f 

i 

f 

29 

• 

• 

t 

t 

• 

• 

• 

30 

t 

• 

31 

• 

32 

• 

• 

33 

34 

35 

10  cm. 

iiiiiiiiiit 


Comparison  of  growth  of  the  Flexner-Jobling  adeno-carcinoma  of  the  rat,  in  normal  control  rats  and  ii 
those  treated  with  mouse  and  cat  sarcoma  19  and  14  days  respectively  before  tumor  implantation 
All  rats  inoculated  with  0.02  gram  of  the  Flexner-Jobling  tumor  2  —  xii  —  07.  There  is  no  pro^ 
taction  induced  by  preliminary  treatment  with  tumors  of  a  strange  species.  I 


RESISTANCE 


143 


Albrecht  and  Hecht  ^  noticed  that  mice  in  which  transplantation 
had  been  unsuccessful  were,  in  general,  more  refractory  than  normal 
animals,  and  in  the  case  of  a  very  virulent  carcinoma  they  had  seen 
this  resistance  in  as  many  as  50  %  of  the  animals,  although  the  phenom- 
enon was  in  no  way  constant.  Such  mice  were  protected  against 
another  strain  also,  but  in  a  lower  degree. 

Active  Resistance  probably  evolved  only  by  Intact  Tumor  Cells  of  the 
Same  Species :  — ■  Having  demonstrated  that  immunity  ensued  upon 
unsuccessful  inoculation,  those  engaged  in  the  study  of  experimental 
cancer  set  themselves  the  task  of  producing  resistance  by  treatment 
with  something  other  than  living  cancer  cells  of  the  same  species,  for 
when  the  mahgnant  cell  was  employed  a  certain  number  of  animals 
developed  tumors,  becoming  thereby  unavailable  for  further  use. 

Michaelis  ^  tried  repeated  inoculations  of  cancer  cells  killed  by 
chloroform  or  heat,  but  reported  that  his  attempts  had  been  fruitless. 
Searching  further,  he  inoculated  white  mice  with  a  gray  mouse  car- 
cinoma and  with  a  carcinoma  from  the  rat,  knowing  that  by 
reason  of  race  specificity  neither  of  these  tumors  would  be  able  to 
grow  in  the  white  mouse ;  but  not  the  slightest  indication  of  resistance 
revealed  itself  in  any  of  the  animals.  Heated  tumor  was  injected 
also  by  Lewin,^  who  could  not  discpver  any  evidences  of  resistance  after 
its  inoculation. 

Although  immunity  was  not  evident  to  Bashfordand  his  colleagues* 
in  mice  inoculated  with  growths  from  other  species,  Lewin^  found  that 
he  could  produce  almost  complete  resistance  in  mice  by  two  inocula- 
tions at  short  intervals — three  to  seven  days  —  with  rat  carcinoma. 
By  preliminary  treatment  with  mouse  carcinoma  he  could  protect 
rats  against  both  carcinoma  and  sarcoma. 

Clowes  ^  said  that  more  than  two  years  before  the  date  of  writing, 

1  Centralbl.  f.  allg.  Path.,  etc.,  1909,  xx,  1039. 

Wien.  klin.  Woch.,  1909,  xxii,  1740. 
^  Med.  Klin.,  1905,  i,  205. 

Zeitschrift  f.  Krebsforsch.,  1907,  v,  192. 

Bed.  klin.  Woch.,  1907,  xliv,  486. 

Dent.  med.  Woch.,  1906,  xxxii,  1728.  See  also  Michaelis,  Fleischmann,  and  Pincus- 
sohn,  Dent.  med.  Woch.,  1907,  xxxiii,  827. 

^  Zeitschrift.  f.  Krebsforsch.,  igoy-igoS,  vi,  ^oS. 
^  British  Med.  Jour.,  1907,  ii,  28. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  365,  368. 
^Berl.  klin.  Woch.,  1907,  xliv,  1606.  ^British  Med.  Jour.,  1906,  ii,  1550. 


144  RESISTANCE 

experiments  had  shown  him  the  futiHty  of  trying  to  produce  immunity 
with  inanimate  materials,  and  that  he  and  his  associates  had  from  the 
first  emphasized  the  role  played  by  the  hving  cell.  On  this  occasion 
he  repeated  his  behef  that  actual  ceU  growth  must  take  place  in  order 
for  immunity  to  be  conferred,  and  placed  in  CAddence  unsuccessful  at- 
tempts to  produce  resistance  \Adth  tumor  cells  that  had  been  de- 
stroyed by  heat  or  treated  with  certain  chemicals,  as  mercuric 
chloride,  potassium  cyanide,  iodine,  etc.  Furthermore,  the  refractory 
state  could  not  be  ehcited  by  inoculating  the  nucleoproteids  or  nucleo- 
histons  extracted  from  tumors. 

That  intact  cells  were  requisite  for  the  production  of  resistance  was 
shown  by  Bridre,^  who  injected  the  clear  fluid  obtained  by  filter- 
ing and  centrifuging  a  tumor  mush.  Growths  developed  in  40  %  of 
the  mice  thus  treated  and  in  50  %  of  the  controls,  while  in  mice  that 
had  been  treated  -^dth  timior  fragments  heated  to  points  exceeding 
50°  C.  there  was  likewise  a  barely  appreciable  immunity  to  implan- 
tation. The  general  result  of  his  investigations  was  that  the  highest 
resistance  followed  the  inoculation  of  uninjured, cells. 

In  perfect  agreement  "^dth  this  conclusion  was  the  observation  of 
Haaland,-  that  the  refractory  state  did  not_supervene  in  mice  inoculated 
with  an  emulsion  of  tumor  cells  de^dtaliged  by  freezing  and  grinding. 

Active  Resistance  Ez'ohed  by  Xormal  Tissue 

A  useful  and  extremely  interesting  method  of  evoking  the  refractory 
condition  was  described  from  Bashford's  laboratory,  where  it  was 
found  that  immunity  would  follow  the  inoculation  of  other  material 
than  tumor.  Thus  he  ^  and  his  co-workers  discovered  that  a  prelimi- 
nary injection  of  from  0.3  to  0.5  cubic  centimeter  of  normal  defi- 
brinated  mouse  blood  induced  a  definite  resistance  even  in  young 
animals.  A  repetition  of  the  treatment  did  not  materially  increase 
the  refractory  condition.  Analysis  of  the  phenomenon  proved  the 
corpuscles  to  be  the  active  agent,  serum  alone  being  impotent,  and  it 
was  further  found  that  the  efl'ect  was  best  brought  out  when  the 

^  Ann.  de  I'lnst.  Past.,  1907,  xsi,  768.  ^  Lance*,  1910,  i,  7S7. 

'  British  Med.  Jour.,  1906,  ii,  209. 

Lancet,  1906,  ii,  315. 

Proc.  Roy.  Soc,  Series  B,  1907,  Ixxix,  iSo. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  333,  369. 


CONTROL     1 19.              20-34  mice  treated                   35-49  mice  treated  with  60-67  mice  treated  with 

Untreated  mice.                 with  0-]  c.c.  embryo                  O'l  c.c.  mamma  emulsion.  005  c.c.  ekin  emulsioD. 
Average  weight                  emulsion  (skinless). 

21 '5  grms.  Average  weight  i2-8  grms.             Average  weight  23  gnus.  Average  weight  19  grml 

28/  5/  12/  19/  28/    2/          28/  6/  12/19/  26/   2/         28/  6/  12/  19/  26/  2/   9/  16/  23/  28/  5/  12/ l9/^'/„  V..  V..  'K. 

/9/I0/I0/I0/IO/II        /9 /lo /lo/io /lo /ii        /s  /IP  /1 0/10  /\o /\\_A>^A\  /I I  A  At)  Ao  At /w/\\ /ji/JL 

I  •    9    9    f   f  20   ,     f   ^^^         ^    '     »    *  ^  f^T^  "    '     '     '    '    ^  f  T  T 

3r#Cf|  22.»«it»37ff^^O  52 

4»t#»  :3'**|.     -aavtc^t^tvtjs 

5    f     r  2l-----3a,<#.  v___-_^ 

6«1tt«  25    ------     40     •••^^^  55   ______ 

7tt***<  23    ------     41     ».»|f|^  5B   ------ 

8.;i  27    ------     12     »Q#t»»»"  57  ------ 

9,.-  2S    ------      43     •••  58    ------ 

IB     »..___  29    ------     44  59    ______ 

II  r  a-.    ...-45.    ----_-.  60  ------ 

12'  Sl._----43i.-...  61    ------ 


13    '      I       -      -      _     -         32    ------      47 

I*     •      -  83   ------       48 

IS     ------34--  49 


64 


11    •     _    -  10  cm. 

I mil  J7  -    -     -     -      -      - 

II    .     .     -    .    . 

*  Macroscopic  metastases  in  lungs. 

Protection  against,  or  hypersensibility  toward,  inoculation  of  a  transplantable  squamous  cell  carcinoma 
induced  by  treatment  with  normal  mouse  tissue  15-16  days  before  tumor  implantation.  All  mice 
inoculated  in  right  axilla  with  0.01-0.02  of  tumor.     First  charting  10  days  later. 


RESISTANCE 


145 


minimal  tumor-forming  dose  was  employed,  a  dose  lying  between  one 
and  two  centigrams.  When  larger  amounts  (five  centigrams)  were 
introduced,  the  percentage  of  growths  in  the  treated  animals  was 
greater,  although  still  not  so  large  as  in  the  controls,  while  in  a  series 
where  massive  doses  were  inoculated,  nodules  developed  eventually, 
although  their  appearance  was  somewhat  delayed.  Here,  the  authors 
thought,  the  larger  dose  of  tumor  had  so  exhausted  the  protection 
that  growth  finally  became  possible. 

Schone,^  working  in  EhrHch's  laboratory,  succeeded  in  producing 
resistance  by  preHminary  injections  of  mouse  embryo,  liver,  or  testis. 
Rather  large  embryos,  emulsified  without  the  addition  of  fluid,  were 
inoculated  in  amounts  of  from  0.3  to  0.7  cubic  centimeter.  White 
mice  were  used  in  all  the  experiments,  and  the  testing  tumor  was 
a  vigorously  growing  alveolar  carcinoma  known  as  "5."  In  the  first 
experiment,  thirteen  animals  were  injected  eight  times  —  six  times 
subcutaneously  and  twice  intraperitoneally  —  during  a  period  of 
seventy-one  days,  the  last  treatment  taking  place  one  day  before  the 
tumor  was  inoculated.  Among  the  thirteen  treated  mice,  46.15  % 
failed  to  develop  tumors,  although  inoculation  was  successful  in  all  but 
7.14%  of  the  twenty-eight  controls.  Not  only  were  there  fewer 
nodules  among  the  treated  mice  than  among  the  untreated,  but  those 
that  did  occur  showed  a  distinct  retardation  of  growth.  In  a  second 
experiment  eighteen  mice  received  two  intraperitoneal  injections  at  an 
interval  of  two  weeks.  Implantation  of  carcinoma  "5,"  undertaken 
fourteen  days  later,  was  followed  by  a  negative  outcome  in  66.67  % 
of  the  eighteen  treated  mice  but  in  only  16.67  %  among  eighteen  con- 
trols, and  of  the  six  tumors  developing  in  the  refractory  animals  only 
two  showed  no  delay  in  their  growth.  The  presence  of  a  higher  degree 
of  resistance  after  eight  injections  than  after  two  could  not  be  sub- 
stantiated. Liver  and  testis,  although  producing  immunity,  were  not 
nearly  so  efficacious  as  embryo.  Whether  the  resistance  evoked  by 
normal  tissues  was  identical  with  that  following  the  inoculation  of 
tumors,  Schone  left  an  open  question. 

In  a  later  article  he  ^   said  that  one  single  subcutaneous  inoculation 

^  Miinch.  rued.  Woch.,  1906,  liii,  2517. 

^  Verhandl.  d.  GeseUsch.  deutscher  Naturforsch.  u.  Aerzte,  1907,  79'""  Versammlung, 
erste  Teil,  304. 


146  RESISTANCE 

of  normal  tissue  would  call  forth  an  efficient  immunity  and  that  intra- 
peritoneal inoculations  were  also  active  in  producing  this  condition, 
although  here  larger  doses  were  preferable  (0.5  to  i.o  cubic  centimeter). 
The  immunity  consequent  upon  the  inoculation  of  spontaneous 
tumors  was,  in  general,  more  marked  than  that  following  prehminary 
treatment  with  embryo  emulsion,  although  the  two  types  seemed 
to  have  a  number  of  characteristics  in  common. 

Investigating  the  prehminary  observations  of  the  authors  just  cited, 
MichaeHs,  Fleischmann,  and  Pincussohn^  succeeded  in  demonstrating 
a  certain  amount  of  resistance  after  three  inoculations  of  an  emulsion 
of  normal  mouse  Hver.  Of  twenty  animals  thus  treated,  only  30  % 
developed  tumors,  while  among  eighteen  controls  there  were  growths 
in  72  %.  As  in  Schone's  experiments,  the  nodules  that  did  appear  in 
the  treated  animals  were  of  retarded  growth  and  attained  only  a  mod- 
erate size,  afterward  remaining  stationary.  Proliferation  in  the  control 
mice,  on  the  other  hand,  was  progressive. 

Borrel  ^  and  Bridre  ^  inoculated  mice  with  blood  and  with  emulsions 
of  spleen,  hver,  or  testis,  in  amounts  of  one  cubic  centimeter.  Two 
inoculations  of  blood,  of  about  0.25  cubic  centimeter  each,  gave  but 
a  feeble  resistance  against  the  Pasteur  Institute  tumor  "B,"  40% 
of  growths  developing  in  treated  animals  compared  with  55  %  in  the 
controls.  Three  inoculations  of  hver  emulsion,  at  intervals  of  twelve 
days,  produced  a  higher  degree  of  immunity,  while  perfect  resistance 
was  obtained  by  the  inoculation  of  spleen.  On  the  other  hand,  testis 
was  quite  powerless  to  ehcit  the  refractory  state,  50  %  of  tumors 
developing  in  the  treated  mice  and  55  %  in  the  controls. 

Lewin  ^  extended  these  studies  to  rats,  and  produced  resistance 
against  his  rat  carcinoma  and  against  Jensen's  rat  sarcoma  by  a  single 
inoculation  with  0.8  to  i.o  cubic  centimeter  of  normal  rat  blood. 

Moreschi,'^  after  the  inoculation  of  an  emiilsion  of  actively  lactating 
mouse  mamma  in  amounts  of  0.15  to  0.20  cubic  centimeter,  found 
conditions    ranging    from    hypersusceptibihty     to    resistance.     The 

1  Dent.  med.  Wock.,  1907,  xxxiii,  827. 

2  Bull,  de  VInst.  Past.,  1907,  v,  605. 

^  Ann.  de  I'Inst.  Past.,  1907,  xxi,  769. 
^  Berl.  klin.  Woch.,  1907,  xliv,  1606. 

ZeUschrift  f.  Krehsforsch.,  1907-1908,  vi,  310. 
^  Zeitschrifl  f.  Immiinitdisforsch.,  etc.,  Orig.,  1909,  ii,  675. 


RESISTANCE  147 

immunity  varied  toward  different  tumors,  a  much  more  refractory 
state  being  present  for  Etulich's  carcinoma  "ii"  than  for  carcinoma 
"  5."  Toward  a  sarcoma  the  resistance  was  often  evidenced  merely  by 
a  retardation  of  growth,  although  at  other  times  80  to  87.5  %  of 
tumors  developed  in  the  resistant  animals  as  compared  with  100  %  in 
the  controls.  The  large  }'ield  was  doubtless  due  to  the  extraordinary 
virulence  of  this  growth. 

The  production  of  resistance  by  the  inoculation  of  normal,  blood  and 
of  embryo  emulsion  was  further  substantiated  by  Uhlenhuth  and 
Weidanz/  but  they  were  unable  to  cause  its  evolution  with  mouse 
lens. 

Higuchi  -  recorded  the  achievement  of  immunity  through  the  intro- 
duction into  mice  of  mouse  placenta,  which  was  capable  of  provoking 
the  condition  quite  independently  of  its  contained  blood.  It  was 
effectual  not  only  against  several  carcinomata  but  against  a  sarcoma 
as  well. 

In  experiments  with  tumors  other  than  Jensen's,  Bashford  and  his 
associates  ^  found  that  injections  of  blood  protected  to  a  lower  degree 
against  their  tumor  "50"  and  hardly  at  all  against  tumors  "32''  and 
"27."  In  these  facts  they  saw  still  further  eAidence  of  the  truth  of 
their  oft-repeated  statement  that  the  conditions  of  growth  were  spe- 
cific for  different  tumors,  and  th'at  factors  unfavorable  to  one  particu- 
lar neoplasm  were  not  necessarily  active  against  aU  other  growths. 

Schone.''  indeed,  had  found  the  limits  of  specificity  so  narrow  that 
the  embryos  of  gray  mice  were  not  as  suitable  as  those  of  white  for 
the  production  in  white  mice  of  immimity  toward  a  white  mouse  tumor, 
although  -^ith  extensive  treatment  a  definite  result  could  be  achieved. 
Rat  embryos,  as  a  rule,  did  not  educe  resistance,  although  in  isolated 
instances  tumor  growth  seemed  to  be  held  somewhat  in  abeyance. 

A  lack  of  specificity  in  the  immune  reaction  was  suggested  also  by  the 
work  of  Rous,^  who  showed  that  resistance  toward  the  implantation 

^  Arb.  a.  d.  Raised.  GesufidheitsanUe,  1909,  xxx,  443. 
^  Sei-I'Kiuai  Medical  Journal,  Tokio,  191 1,  xxx,  91. 

Fifth  Sci.  Report,  Imperial  Cancer  Research  Fimd,  London,  191 2,  Sy 
'  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  375. 
^  Verhandl.  d.  Gesellsch.  deutscher  N atiirforsch.  u.  Aerzte,  1907,  79'''''  Versammlung,  erste 
Teil,304. 

^  Jour  E.xp.  Med.,  1910,  xii,  344. 


148  RESISTANCE 

of  fetal  cells  could  be  produced  by  the  inoculation  of  embryonic  tissue, 
and  that  it  was  manifest  in  an  absence  of  the  stroma  reaction  neces- 
sary for  a  temporary  survival  of  the  ingrafted  material.  , 

Active  Resistance  probably  evolved  only  by  Intact  Normal  Cells  of  the 
Same  Species :  —  Just  as  resistance  to  subsequent  inoculation  fails  to 
foUowjDTeKminar}^  treatment  with  tumor  cells  robbed  of  their  vitality 
by  heat  or  other  injurious_agents,  or  -with  intact  tumor  cells  of  different 
species,  so  in  the  case  of  normal  tissue  is  the  injection  of  uninjured 
li\ing  cells  of  the  same  species  an  essential  for  the  production  of  the 
resistant  state. 

Bashford  and  his  associates  ^  were  unable  to  prevent  the  growth 
of  transplanted  cancer  in  mice  by  the  inoculation  of  the  normal  tissues 
of  rats,  rabbits,  guinea-pigs,  or  more  distantly  related  species,  and 
Higuchi  -  discovered  little  if  any  inhibitory  effect  after  the  introduc- 
tion into  mice  of  placenta,  blood,  mammary  gland,  embryo  skin,  or 
spleen  of  rats  and  guinea-pigs. 

In  the  experiments  of  Moreschi,'^  although  rat  mamma  produced 
not  a  trace  of  immunity  in  mice  against  one  mouse  carcinoma,  it 
was  efficacious  against  a  second  one,  and  he  thought  that  the  presence 
of  the  refractory  condition  depended  upon  the  length  of  time  elaps- 
ing between  inoculations,  no  less  than  upon  certain  other  factors. 
Proceeding  to  test  the  power  of  rat  sarcoma  to  effect  resistance  in 
mice,  he  discovered  evidence  that  such  a  condition  had  been  induced. 
Lactating  guinea-pig  mamma  was  also  active,  but  not  in  so  high  a 
degree  as  mouse  mamma.  He  concluded,  therefore,  that  Bashford 
and  his  associates  were  not  justified  in  denying  the  possibihty  of 
producing  resistance  with  the  tissues  of  strange  species. 

Similar  results  were  cited  by  Apolant,^  who  wrote  that  by  treatment 
with  alien  blood  he  had  occasionally  obtained  immunity  against  mouse 
carcinoma,  and  that  he  was,  therefore,  unable  to  agree  with  Bashford's 
contention  that  only  tissues  of  the  same  species  were  potent. 

^  British  Med.  Jour.,  1907,  ii,  28. 

Proc.  Roy.  Soc,  Series  B,  1907,  Ixxix,  182. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  334,  365,  376. 
2  Sei-I-Kwai  Medical  Journal,  Tokio,  1911,  xxx,  91. 

Fifth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  191 2,  85. 
^  Zeitschrift  f.  Immunildtsforsch.,  etc.,  Orig.,  1909,  ii,  681. 
^ Zeitschrift  f.  allg.  Physiol.,  1909,  ix,  Sammelreferat,  91. 


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RESISTANCE 


the  inoculation  of  fluids  expressed  from  the  organs  of  normal  or 
tiunor-bearing  mice ;  nor  was  the  injection  of  alien  albumin  fol- 
lowed by  the  occurrence  of  immunity. 

Since  the  majority  of  the  \'ital  functions  of  the  cell  were  elaborated 
by  its  endocellular  enzymes,  which  were  best  hberated  by  autolysis. 
Levin  ^  tried  to  produce  the  refractory  state  in  rats  by  previous  treat- 
ment with  autolyzed  rat  Hver.  As  a  certain  amount  of  immunity 
became  evident,  he  assumed  that  there  may  have  been  present  some 
endocellular  enzyme-like  substances  which  autolysis  had  been  powerless 
to  injure. 

No  Active  Resistance  with  Autologous  Tissue:  —  It  was  at  first 
thought  by  Woglom  -  that  resistance  toward  transplanted  cancer  could 
be  provoked  in  a  mouse  by  the  inoculation  of  its  own  spleen,  but  more 
extended  observation  con^inced  him  ^  that  neither  the  spleen  nor  any 
other  of  the  various  organs  or  combinations  of  organs  with  which  he 
worked  could,  when  inoculated  into  the  mice  from  which  the}'  had  been 
removed,  render  the  animals  refractory  to  the  subsequent  transplanta- 
tion of  a  tumor. 

In  the  meantime  the  subject  had  been  approached  by  Apolant  and 
Marks,"*  who  concluded  that  the  spleen  did  not  contain  enough  tissue 
to  }deld  an  amount  sufficient  for  the  induction  of  the  resistant  state ; 
but  whether  or  not  an  animal  could  be  made  refractory  by  the  inocu- 
lation of  its  own  tissues,  pro\ided  a  large  enough  dose  were  available, 
they  preferred  to  leave  an  open  question. 

Lambert  ^  was  unable  to  detect  any  evidence  of  immunity  in  mice 
injected  with  their  own  blood  corpuscles. 

Can  Tumor-hearing  Animals  he  made  Actively  Resistant? 

It  was  suggested  by  Schone  ^  that  it  might  be  impossible  to  pro- 
voke a  condition  of  resistance  to  transplantable  tumors  in  a  mouse 
already  bearing  a  propagable  growth.     Mice  in  which  a  transplantable 

^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1909-1910,  vii,  64. 
^  Jour.  Exp.  Med.,  1910,  xii,  29. 

^  Zeitschrift  f.  Immunitatsforsch.,  etc.,  Orig.,  1911,  xi,  683. 

^  Zeitschrift  f.  lynmunitatsforsch.,  etc.,  Orig.,  1911,  x,  159.  See  also  Apolant,  Zeitschrift 
f  Immunitatsforsch.,  etc.,  Orig.,  191 2,  xii,  472. 

^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1911-1912,  ix,  18. 
^  Verhandl.  d.  deutschen  Gesellsch.f.  Chir.,  1907,  xxxvi,  214. 
Dent.  med.  Woch.,  1907,  xxxiii,  866. 


EESISTANCE 


151 


tumor  was  growing  rapidly  were  inoculated  with  spontaneous  hemor- 
rhagic tumors  and  at  the  end  of  a  certain  period,  within  which  nor- 
mal animals  would  have  developed  resistance,  the  growing  tumors  were 
removed.  After  the  resulting  wounds  had  healed,  secondary  inocu- 
lations were  undertaken  which,  in  the  great  majority  of  the  animals, 
were  successful.  Nevertheless,  the  procedure  had  been  so  complicated, 
and  the  number  of  mice  so  small,  that  Schone  did  not  wish  to  draw 
any  definite  conclusion,  preferring  to  await  the  outcome  of  further 
experiments. 

Bashford,  Murray,  and  Haaland^  encountered  similar  results,  but 
because  of  the  cardinal  importance  of  dosage  and  time  interval  and 
the  complex  nature  of  the  experiments,  they  found  it  difficult  to 
interpret  the  outcome,  referring  to  the  fact  that  investigation  was  still 
in  progress.  They  had  occasionally  met  with  the  anomalous  finding 
that  treatment  which  in  normal  animals  would  induce  a  powerful 
resistance  to  inoculation,  might  provoke  a  relative  h3^ersensibility  in 
those  bearing  transplanted  growths. 

This  question  has  been  definitely  settled  by  Russell,^  at  least  in  so 
far  as  it  concerns  the  more  slowly  growing  tumors.  Among  sixty-five 
mice  bearing  propagable  growths,  63  %  were  found  to  be  receptive  to 
a  second  inoculation.  This  figure,  however,  was  reduced  in  seventy 
mice  to  27%,  when  the  secoiidary  transplantation  was  preceded  some 
fourteen  to  sixteen  days  by  an  immunizing  injection  of  tumor  or 
mouse  embryo  emulsion. 

Whether  or  not  an  animal  can  be  made  refractory  to  the  re-inocula- 
tion of  a  tumor  which  has  arisen  in  it  spontaneously,  is  of  supreme 
importance,  since  it  concerns  the  search  for  a  means  of  preventing  the 
growth  of  metastatic  deposits.  Haaland  ^  found  that  methods 
which  would  render  normal  mice  resistant  would  prevent  neither  lo- 
cal recurrence  after  operation  nor  the  development  of  new  tumors, 
nor  could  he  influence  by  the  same  means  either  dissemination,  with 
the  consequent  appearance  of  metastatic  nodules  in  the  lungs,  or  suc- 
cessful grafting  of  the  mouse  with  its  own  tumor  cells  (artificial  metas- 

1  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  392. 
"^  Fifth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  191 2,  29. 
^  Jour.  Path,  and  Bad.,  1910,  xiv,  407. 

Proc.  Roy.  Soc,  Series  B,  1910-1911,  Ixxxiii,  540. 

Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1911,  79. 


152  RESISTANCE 

tasis).  There  seemed,  therefore,  to  be  an  insensibility  of  the  cell  in 
its  own  animal  to  reactions  which  were  effective  against  strange  cells 
in  the  same  surromidings.  The  difificulty  was,  as  Haaland  indicated, 
one  which  was  encoimtered  in  all  other  forms  of  cellular  immunity  — • 
that  of  immunizing  against  cells  belonging  to  the  same  organism.  He 
investigated,  in  this  connection,  the  nearest  approach  to  autoplastic 
transplantation  occurring  imder  natural  conditions  i.e.  the  embed- 
ding of  the  ovum  on  the  uterine  mucosa,  and  found  this  process  as 
Httle  influenced  by  methods  effective  against  the  transplantation  of 
cancer  as  was  the  inoculation  of  a  tumor  into  the  animal  to  which  it 
was  native. 

Still  another  phase  of  the  question  has  been  approached  by  the 
same  author.  If  there  was  difficulty  in  producing  resistance  in  an 
animal  bearing  a  transplantable  tumor,  what  conditions  obtained  when 
one  tried  to  produce  resistance  against  a  transplantable  tumor  in  a 
mouse  already  the  subject  of  a  spontaneous  growth  ?  Haaland  ^  found 
that  in  animals  suffering  from  spontaneous  tumors  the  absorption  of 
carcinoma  "206"  went  on  exactly  as  it  did  in  normal  mice,  whence  it 
was  plain  that  in  mice  spontaneously  affected  with  cancer  there  existed 
no  condition  capable  of  preventing  or  of  nulKfying  resistance  toward  a 
transplantable  growth. 

Premetastatic  Stage  of  Active  Resistance 

In  animals  bearing  transplanted  tumors,  resistance  to  re-inocula- 
tion has  been  said  by  some  observers  to  be  present  for  a  certain  period 
after  the  primary  implantation.  This  period  corresponded  to  the  time 
which  elapsed  before  the  appearance  of  metastases,  and  was  described 
first  by  Sticker  -  in  the  dog  as  the  premetastatic  stage.  After  about 
thirty  days  the  resistance  was  said  to  disappear,  so  that  the  taking 
of  a  second  graft  or  the  estabhshment  of  metastases  became  possible. 

The  presence  of  this  stage  in  mice  Bridre  ^  was  unable  to  confirm, 
for  in  his  experiments  animals  bearing  tumors  of  different  ages  were 
all  equally  sensitive  to  re-inoculation. 

1  Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1911,  83. 
^  Miinch.  nied.  Woch.,  1906,  liii,  1904. 

Dent.  med.  Woch.,  1907,  xxxiii,  867. 

Zeitschrift  f.  Krebsforsch.,  1908-1909,  vii,  64. 
^  Ann.  de  Vlnst.  Past.,  1907,  xxi,  773. 


RESISTANCE  1 53 

Flexner  and  Jobling  ^  were  of  the  same  opinion,  and  wrote  that  inocu- 
lation of  their  rat  tumor  succeeded  as  well  in  rats  where  no  visible 
secondary  growths  had  occurred  as  in  those  where  metastasis  had 
already  taken  place. 

Gay,"  in  observations  upon  the  Flexner- Jobling  rat  tumor,  found 
that  if  a  growth  were  removed  during  the  premetastatic  stage  a 
second  graft  would  seldom  grow,  although  after  the  expiration  of  this 
period  proHferation  would  occur  in  the  tumor  secondarily  inoculated. 
If  the  primary  nodule  were  left  and  a  second  graft  implanted  during 
the  premetastatic  period,  not  only  did  the  second  tumor  fail  to  grow, 
but  in  many  instances  the  first  one  disappeared.  The  length  of  the 
premetastatic  period  Gay  put  at  about  thirty  days. 

Jobling,^  however,  working  with  the  same  tumor,  achieved  exactly 
opposite  results.  Re-inoculation  was  possible  during  the  first  thirty 
days  in  all  those  rats  in  which  the  first  growth  was  not  receding,  while 
in  some  rats  with  growing  tumors  inoculation  undertaken  at  a  later 
date  was  not  successful. 

Distribution  of  Active  Resistance 

Acquired  resistance  has  been  studied  in  relation  to  its  distribution 
through  the  organism,  and  Bashford  ^  reported  that  mice  injected  with 
blood  were  immune  to  tumor  implantation  in  locations  remote  from 
that  in  which  the  immimizing  treatment  had  been  undertaken.  More- 
over, it  was  found  by  Bashford,  Murray,  and  Cramer,^  that  mice 
immune  after  recovery  from  experimental  cancer  had  undergone  some 
change  which,  instead  of  being  confined  to  the  tissues  in  the  immedi- 
ate neighborhood  of  the  spontaneously  absorbed  tumor,  had  become 
generalized,  probably  by  means  of  the  body  fluids.  In  the  opinion  of 
Da  Fano,^  the  lym|)hocyte  rnight  be  the  agent  which  distributed 
immunity  throughout  the  organism. 

1  Jour.  American  Med.  Assoc,  1907,  xlviii,  420. 

^  Proc.  Soc.  Exp.  Biol,  attd  Med.,  1908-1909,  vi,  75. 

Boston  Med.  atid  Surg.  Jour.,  1909,  clxi,  207. 
^  Monographs  on  Medical  and  Allied  Subjects,  Rockefeller  Institute,  New  York,  1910, 
No.  I,  57. 

*  British  Med.  Jour.,  1906,  ii,  209. 

Lancet,  1906,  ii,  315. 
^  Proc.  Roy.  Soc,  Series  B,  1907,  Ixxix,  177. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  330. 
^  Zeitschrift  f.  Immunitatsforsch.,  etc.,  Orig.,  1910,  v,  68. 


154  RESISTANCE 

Kraus.  Ranzi,  and  H.  Ehrlich  ^  suggested,  on  the  other  hand,  that 
in  animals  made  refractory  by  subcutaneous  inoculation  the  immu- 
nity was,  perhaps,  a  local  condition  confined  to  the  subcutis,  rather 
than  one  of  wide  distribution  throughout  the  body. 

The  obser^'ation  of  Bashford,  ^Murray,  and  Cramer  was  confirmed 
by  Uhlenhuth.  Haendel,  and  Stefi'enhagen.^  These  authors  found  that 
rats  which  had  become  resistant  by  reason  of  an  unsuccessful  sub- 
cutaneous implantation  could  not  be  inoculated  by  the  peritoneal 
route,  and  that  resistance  in  these  animals  was  thus  not  hmited  to  the 
subcutis. 

Entirely  in  accord  A^'ith  these  observations  were  those  of  Woglom,^- 
who  demonstrated  that  mice  made  refractory  by  the  subcutaneous 
inoculation  of  embryo  skin  were  as  resistant  to  intrarenal  as  to  sub- 
cutaneous grafts  of  a  carcinoma. 

According  to  Le\dn,^  also,  rats  immunized  by  unsuccessful  subcu- 
taneous inoculation  of  a  sarcoma  were  resistant  to  inoculation  into  a 
parench\Tnatous  organ. 

First  Appearance  and  Duration  of  Active  Resistance 

Discussing  the  time  of  appearance  and  the  duration  of  the  refrac- 
tory state,  EhrHch  ^  wrote  that  the  resistance  produced  in  mice  by  the 
unsuccessful  inoculation  of  spontaneous  tumors  appeared  in  from 
seven^  to  fourteen  days,  and  lasted  for  weeks  or  even  months. 

Bashford.^  in  describing  the  resistance  present  after  the  spontaneous 
absorption  of  transplantable  mouse  tumors,  said  that  it  persisted  for 
at  least  six  months. 

Bridre  "  tested  the  duration,  not  only  of  the  resistance  consequent 
upon  unsuccessful  tumor  inoculation,  but  of  that  entailed  by  treat- 
ment \^dth  normal  tissue,  and  concluded  that  acquired  immunity 
in  the  mouse  might  endure  for  five  months  or  more. 

According  to  Bashford.  ^Murray,  and  Cramer,^  the  resistance  attend- 

^  Zeitschrijl  f.  I mmunitatsforsch. ,  .etc.,  Orig.,  1910,  vi,  681. 

^  Arh.  a.  d.  Kaiserl.  Gesundheitsamte,  1911,  xxx\a,  484. 

^Lancet,  1911,  ii,  92.  ^  Jour.  Exp.  Med.,  1911,  xiv,  139. 

^  Zeitschrift  f.  aerztliche  Fortbildung,  1906,  iii,  211. 

Arb.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  90,  97. 
^  British  Med.  Jour.,  1906,  ii,  209.  ^  Ann.  de  I'lnst.  Past.,  1907,  xxi,  773. 

^  Proc.  Roy.  Soc,  Series  B,  1907,  Ixxix,  180. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  333. 


RESISTANCE 


155 


ant  upon  the  inoculation  of  mousejblood  appeared  after  four  days,  but 
was  more  marked  after  ten.  Embryo  skin  required  twenty  days  to 
elicit  the  refractory  state  in  Russell's  experiments/  or  twice  the  time 
consumed  by  blood. 

In  the  rat,  Uhlenhuth,  Haendel,  and  Steffenhagen  ^  discovered  evi- 
dence of  immunity  a  month  and  a  half  after  absorption  of  a  spindle 
cell  rat  sarcoma,  while  Flexner  and  Jobling^  found  that  the  resist- 
ance  left  by  the  retrogression  of  growing  tumors,  although  not  perfect, 
was  of  high^  degree,  and  that  it  was  mosLmarkedjmrnediately  after 
the  disapjjgarance  of  the  tumors,  becoming  reduced  subsequently  by 
mere  lapse  of  time.  Within  a  period  of  ninety  days  after  the  retro- 
gression of  adeno-carcinomata  in  sixty-one  rats,  16.5%  of  the  animals 
proved  re-inoculable  with  a  tumor  which,  in  the  control  animals, 
yielded  86.2  %  of  growths. 

Woglom^  has  investigated  the  onset,  extent,  and  duration  of  the 
resistance  produced  in  mice  by  0.05  cubic  centimeter  of  embryo  skin, 
normal  kidney,  or  spontaneous  carcinoma.  The  immunity  following 
treatment  with  embryo  skin  reached  its  maximum  of  80-100% 
by  the  tenth  day,  remained  at  a  high  level  until  the  twenty-fourth, 
and  then  declined,  to  vanish  at  about  the  seventy-fifth  day.  Neither 
kidney  nor  spontaneous  tumors  produced  so  high  a  degree  of  re- 
sistance. 

Passive  Resistance 

The  presence  in  the  serum  of  resistant  mice  of  some  factor  deleterious 
to  the  growth  of  malignant  elements  was  at  once  suggested  when 
Clowes  and  Baeslack  ^  asserted  that  exposure  of  cancer  cells  to  immune 
serum  before  inoculation  inhibited  their  subsequent  development. 
The  great  majority  of  investigators,  however,  have  been  unable  to 
demonstrate  inimical  substances  in  the  serum  either  in  vitro  or  in  vivo, 
although  V.  Dungern  ^  has  described  the  transfer  of  resistance  to  rabbits 
through  the  serum  of  others  that  had  spontaneously  recovered  from  a 

1  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  345. 
^  Cenlralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Ref.,  1910,  xlvii,  Beiheft,  164. 
3  Monographs  on  Medical  and  Allied  Subjects,  Rockefeller  Institute,  New  York,  rgio. 
No.  I,  54. 

*Jour.  Exp.  Med.,  191 2,  xvi,  629.  ^  Med.  News,  1905,  Ixxxvii,  969. 

^  Zeitschrift  f.  Itnmunitdtsforsch.,  etc.,  Orig.,  1910,  v,  695. 


156  RESISTANCE 

transplantable  sarcoma.  Twelve  to  twenty  cubic  centimeters  were 
injected  into  the  aural  vein  in  six  animals  simultaneously  with  the 
tumor,  and  in  one  twenty-four  hours  previously.  In  these  seven  rab- 
bits no  tumors  arose,  although  six  developed  among  nine  controls. 

But  in  the  opinion  of  Apolant,-^  this  growth  was  hardly  analogous 
to  the  blastomata  hitherto  studied,  and  as  it  was  in  all  probabiHty  of 
parasitic  nature  Apolant  thought  that  v.  Dungern's  results  should  be 
accepted  with  caution. 

The  production  of  passive  resistance  in  mice  by  means  of  serum 
drawn  from  rabbits  injected  with  mouse  cancer  was  attempted  by 
Michaelis.^  Although  this  serum  was  hemolytic  for  mouse  blood,  it 
possessed  no  immunizing  action  against  cancer. 

Ehrhch  ^  mixed  tumor  emulsion  with  the  serum  of  treated  rabbits, 
but  was  not  able  to  perceive  that  the  serum  exerted  any  effect  upon 
the  cancer  cells. 

Haaland  ^  found  that  the  serum  of  mice  which  had  been  inoculated 
with  Jensen's  tumor  was  powerless  to  confer  resistance  against  a  sar- 
coma. He  furthermore  injected  the  serum  of  naturally  resistant 
Hamburg  mice  into  young,  susceptible  mice  from  Berhn,  but  dis- 
covered no  difference  between  the  treated  animals  and  the  controls 
upon  subsequent  inoculation  with  a  sarcoma.  Similarly,  Gay  ^  wrote 
that  the  serum  of  rats  unsuccessfully  implanted  with  the  Flexner- 
JobHng  rat  tumor,  or  naturally  refractory  to  it,  did  not  prevent  growth 
if  introduced  simultaneously  with  the  tumor. 

Bridre  ^  treated  sheep  and  fowl  with  fresh  cancer,  and  with  pre- 
liminary injections  of  their  serum  sought  to  prevent  the  estabUshment 
of  tumor  grafts  in  mice.  The  results  were  not  encouraging,  and 
among  the  mice  inoculated  with  the  specific  sheep  serum  there  de- 
veloped a  number  of  tumors  even  greater  than  occurred  among  the 
controls. 

Bashford,  Murray,  and  Haaland  "^  had  not  been  able  to  demonstrate 
directly  any  antibodies  in  the  serum  or  in  the  milk  of  mice  naturally 

^  Zeitschrift  f.  Krebsforsch.,  1911-1912,  xi,  106.  ^  Med.  Klin.,  1905,  i,  205. 

^  Zeitschrift  f.  Krebsforsch.,  1907,  v,  75.  ^  Berl.  kliti.  Woch.,  1907,  xliv,  717. 

^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1908-1909,  vi,  75. 

Boston  Med.  and  Surg.  Jour.,  1909,  clxi,  210. 
^  Ann.  de  VInst.  Past.,  1907,  xxi,  774. 
^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  395,  369. 


RESISTANCE 


157 


or  artificially  refractory  to  cancer,  nor  could  they,  by  inoculating  the 
blood  of  resistant  mice,  cause  the  development  of  a  higher  degree  of 
immunity  than  could  be  obtained  with  the  blood  of  normal  mice. 

Uhlenhuth,  Haendel,  and  Steffenhagen  ^  made  frequent  re-inocula- 
tions of  immune  rats  to  increase  resistance  to  the  highest  point,  so 
that  the  presence  of  any  protective  bodies  existing  in  the  blood  might 
be  demonstrated.  But  when  the  serum  was  injected  into  rats  several 
days  antecedent  to  tumor  inoculation,  or  allowed  to  act  upon  a  tumor 
emulsion  for  half  an  hour  before  its  injection,  no  evidence  of  any  pro- 
tective substance  was  discovered ;  on  the  contrary,  Uhlenhuth  and 
his  associates  found  that  tumor  growth  was  favorably  influenced. 

Finally,  Russell  ^  came  to  the  conclusion  that  there  were  no  features 
in  the  immune  condition  comparable  to  the  antibodies  evolved  against 
the  infective  organisms. 

While  the  experience  of  nearly  all  those  who  have  investigated  the 
question  is  thus  arrayed  against  the  possibihty  of  transferring  resist- 
ance from  one  animal  to  another,  authorities  are  still  not  entirely 
unanimous  upon  this  point,  and  Gaylord  ^  has  but  newly  reaffirmed  his 
belief  that  passive  immunity  to  cancer  does  actually  exist,  even  though 
it  be  not  easily  or  always  a  demonstrable  condition. 

ARE   NATURAL   AND    ACQUIRED   RESISTANCE   TRANSMISSIBLE   BY 

HEREDITY  ? 

The  hereditary  transmission  of  natural  resistance  to  transplanted 
tumors  was  tested  by  Tyzzer,^  who  found  that  the  offspring  of  natu- 
rally immune  mice  were  more  refractory  than  controls  of  the  same  age.'^ 

The  opposite  condition,  susceptibiUty,  which  had  been  vouched  for 
by  Morau,^  was  also  investigated  to  see  whether  it  was  regularly 
transmitted  from  generation  to  generation,  or  inherited  as  a  Mendehan 
character.      Most  of  Tyzzer's  experiments  were  performed  with  the 

^  Arh.  a.  d.  Kaiserl.  Gesundheitsamte,  1911,  xxxvi,  490. 

^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  357. 

^  Travaux  de  la  deuxietne  Conference  internal,  pour  l' Etude  du  Cancer,  Paris,  191 1,  594. 

^  Jour.  Med.  Research,  1909,  N.S.,  xvi,  519. 

^  Clowes  {Johns  Hopkins  Hosp.  Bnll.,  1905,  xvi,  130),  however,  had  recorded  the  oc- 
currence of  ten  rapidly  growing  tumors  among  sixteen  young  mice,  descendants  of  parents 
not  susceptible  to  the  Jensen  tumor. 

^  Arch,  de  Med.  exp.  et  d'Anat.  path.,  1894,  vi,  692. 


1^8  RESISTANCE 

spontaneous  growth  of  a  Japanese  waltzing  mouse,  although  the  Jensen 
carcinoma  and  a  tumor  from  EhrHch's  laboratory  were  also  used.  The 
waltzing  mouse  tumor  grew  from  the  first  in  practically  all  Japanese 
waltzing  mice,  whereas  repeated  implantations  into  ordinary  mice  were 
unsuccessful.  The  cross-breeding  of  Japanese  waltzing  mice  and  com- 
mon mice  was  undertaken,  therefore,  for  the  purpose  of  testing  the 
susceptibility  of  the  offspring  so  produced.  The  hybrids  of  the  first 
generation  were  susceptible,  both  the  progeny  of  common  and  of 
Japanese  waltzing  mothers ;  susceptibiHty,  accordingly,  might  be  trans- 
mitted by  either  the  male  or  the  female  parent.  But  the  members, 
of  the  next  generation,  obtained  by  breeding  the  hybrids  among  them- 
selves, were  all,  like  common  mice,  insusceptible.  The  appearance  of 
susceptibility  in  the  first  generation  and  its  total  disappearance  iii  sub- 
sequent generations  Tyzzer  was  unable  to  harmonize  with  Mendel's 
law,  or  with  any  other  principle  of  heredity  yet  known.  Although  a 
certain  number  of  the  mice  of  the  second  and  third  generations  man- 
ifested the  waltzing  character,  they  were  nevertheless  insusceptible  to 
the  waltzing  mouse  tumor,  while  the  hybrids  of  the  first  generation,  al- 
though none  of  them  exhibited  the  waltzing  character,  were  susceptible. 

Cuenot  and  Mercier  ^  also  have  asserted  that  a  condition  of  natural 
suitabihty  for  the  inoculation  of  tumors  could  be ,  transmitted  to  the 
offspring.  Every  mouse,  they  concluded,  was  able  to  transmit  to  its 
descendants  a  certain  sensitiveness  to  the  implantation  of  a  tumor 
graft.  These  observers  succeeded  in  breeding  two  strains  of  mice  — 
a  susceptible  and  a  non-susceptible  strain.  The  non-susceptible 
group  comprised  one  hundred  and  three  mice,  of  which  seventeen 
(16.5  %)  were  successfully  inoculated  with  Borrel's  tumor  ''B."  Of 
the  susceptible  strain  there  were  eighty-nine,  which  were  inoculated  at 
the  same  time  as  the  non-susceptible  mice  and  with  fragments  of  the 
same  tumor.     Of  these,  seventy-six  (85.3  %)  developed  growths. 

The  question  of  the  transmission  of  acquired  resistance  from  a  re- 
fractory mother  to  her  young  has  been  answered  in  the  negative  by 
Bashford,  Murray,  and  Haaland,"  who  inoculated  the  offspring  of  mice 
that  had  been  rendered  highly  resistant  by  repeated  treatment  with 

^  Compt.  rend,  de  VAcad.  des  Sc,  1910,  cl,  1443. 

Compt.  rend.  Soc.  Biol.,  1910,  Ixix,  645.    . 
2  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  395. 


RESISTANCE 


159 


large  doses  of  Jensen's  tumor.  Twenty-one  of  these  young  mice, 
when  implanted  with  Jensen's  tumor,  did  not  show  themselves  any  more 
refractory  to  it  than  other  mice  of  the  same  age. 

These  results  correspond  to  those  of  Cuenot  and  Mercier,^  who 
were  unable  to  demonstrate  resistance  in  the  young  born  of  a  mother 
in  which  the  tumor  had  been  absorbed  during  lactation. 

NATURE    OF   THE   RESISTANT   STATE 

Although  resistance  to  the  implantation  of  cancer  is  such  a  well- 
recognized  condition,  no  attempt  to  explain  its  character  has  so  far 
been  accepted  on  all  sides  as  complete  and  satisfactory. 

The  most  widely  criticized  and  skilfully  defended  hypothesis  among 
those  essaying  to  explain  the  nature  of  resistance  has  been  EhrKch's 
hypothesis  of  atltre^sia  which,  advanced  by  its  disJinguMied^sponsor" 
as  the  result  of  the  following  chain  of  reasoning,  has  been  re-stated  and 
defended  in  a  series  of  subsequent  articles.^ 

A  mouse  carcinoma  is  able  to  prohferate  to  a  certain  extent  in  the 
rat,  retrogressing,  however,  in  about  a  week.  If,  at  the  height  of  its 
activity,  such  a  tumor  were  to  be  inoculated  into  a  second  rat,  no 
further  growth  would  take  place,  whereas  if  it  were  inoculated  back 
into  a  mouse  continuation  of  growth  would  become  possible.  One 
could  practise  such  zigzag  inoculation,  mouse  —  rat  —  mouse  —  rat, 
etc.,  as  long  as  desired,  without  influencing  in  the  least  the  prohfera- 
tive  power  of  the  tumor.  At  first  it  might  be  thought  that  the  in- 
ability of  the  cells  to  grow  progressively  in  the  rat  was  the  result  of 
natural  resistance,  that  is,  of  the  presence  of  antibodies  able  to  exert 
a  direct  lethal  action  on  the  mouse  tumor  cells.  This  h3^othesis 
might  be  dismissed,  however,  without  further  consideration,  for  the 
initial  active  growth  of  the  cells  after  their  introduction  into  the  rat 
would  still  be  inexplicable.  A  second  possibility  was  conceivable : 
That  antibodies  were,  indeed,  present,  but  that  they  were  not  elabo- 

^Compt.  rend,  de  I'Acad.  des  Sc,  1909,  cxlix,  1013. 
^  Zeitsckrift  f.  aerztliche  Fortbildung,  1906,  iii,  208. 
^  Arb.  a.  d.  Konigl.  Inst.  f.  E.xp.  Therap.,  1906,  Heft  i,  83. 

Zeitschrift  f.  Krebsforsch.,  1907,  v,  76. 

Harben  Lecture,  London,  June,  1907;  Jour.  Royal  Inst.  Pub.  Health,  1907,  xv,  321,  385, 
449. 

Beitr.  zur  experimentellen  Pathologic  u.  Chemother apie,  Leipzig,  1909,    77,  134. 


l6o  RESISTANCE 

rated  until  after  the  absorption  of  the  tumor  cells,  and  that  then  only 
was  the  rat  made  actively  refractory.  But  even  this  did  not  suffice 
to  explain  the  phenomenon,  for  it  would  still  be  asked  how  re-inocu- 
lation into  the  mouse  was  possible,  not  the  slightest  damage  having 
been  done  to  the  proliferative  power  of  the  cells  during  their  sojourn 
in  the  rat. 

Much  more  satisfactory  was  a  third  hypothesis,  illustrated  by  an 
example  from  the  domain  of  bacteriology.  When  the  bacillus  of  in- 
fluenza was  cultivated  from  the  sputum,  the  first  culture  was  usually 
successful;  and  while  one  subculture  could  be  made  occasionally 
from  the  original,  further  transplants  were  never  possible  unless  blood-' 
agar  were  used.  For  the  growth  of  the  influenza  bacillus  there  was 
necessary,  therefore,  a  specific  incitant  over  and  above  the  ordinary 
nutrient  material  as  it  existed  in  agar.  While  at  the  time  of  the  first 
subculture  this  condition  was  fulfilled  through  the  presence  of  hemor- 
rhagic sputum,  growth  of  the  bacillus  in  subsequent  cultures  became 
impossible  by  reason  of  exhaustion  of  the  supply  of  specific  material. 
The  situation  was  similar  when  a  mouse  tumor  had  been  transferred 
to  the  rat,  although  here  the  difficulty  could  not  be  lack  of  nourish- 
ment in  a  banal  sense,  for  the  vigorous  growth  during  the  first  week 
was  opposed  to  such  a  conception.  It  was  clear,  therefore,  that  not 
only  was  there  absent  from  the  rat's  organism  an  antistuff  against  the 
cells  of  the  mouse  carcinoma,  but  that  this  host  actually  offered  nour- 
ishment in  abundant  amount,  making  active  proliferation  possible. 
Apparently,  however,  the  presence  of  an  ordinary  food-stuff  did  not 
suffice  for  the  continued  growth  of  the  foreign  cell,  and  just  as  the  in- 
fluenza bacillus  needed  in  addition  to  the  agar  a  small,  amount  of 
hemoglobin,  so  did  the  mouse  carcinoma  require  a  certain  specific 
X-stnf  which  was  present  only  in  the  organism  of  the  mouse,  and  of 
which  a  little  had  been  carried  over  into  the  rat  at  the  first  inocula- 
tion. The  tumor  grew  in  proportion  to  the  amount  of  this  material 
inoculated  with  it ;  but  once  the  supply  became  exhausted,  further 
growth  was  possible  only  if  the  graft  were  returned  to  an  organism 
containing  the  necessary  X-stuff,  i.e.  the  mouse,  and  the  natural  resis- 
tance of  the  rat  might  thus  be  referred  to  lack  of  a  substance  indispen- 
sable for  proliferation  of  mouse  cancer  cells.  The  X-stuff,  how- 
ever, need  not  be  actually  wanting  in  refractory  animals,  for  it  might 


RESISTANCE  l6l 

be  present,  although  not  available,  nor  was  athreptic  immunity,  even 
when  extant,  always  able  entirely  to  prevent  growth.  Proliferation 
might,  indeed,  occur  in  spite  of  it,  although  in  such  a  case  the  tumors 
would  be  of  insignificant  size. 

Ehrlich  was  impressed  by  the  relative  infrequency  with  which 
macroscopic  metastases  were  encountered  in  the  lungs  of  mice  with 
tumors,  and  by  the  observation  that  if  the  formation  of  metastases 
were  imitated  in  animals  already  bearing  rapidly  growing  nodules  by 
re-inoculating  them  with  the  same  or  with  another  tumor,  the  second 
implantation  would  be  unsuccessful  except  in  a  few  instances.  This 
outcome  was  most  readily  explained  by  the  existence  of  the  first  tumor 
which,  during  its  rapid  growth,  devoured  with  a  thousand  mouths  the 
nourishment  that  it  required,  leaving  none  for  cells  secondarily 
inoculated,  or  deposited  as  emboli.  These  elements  found  themselves, 
therefore,  under  much  more  adverse  nutritive  conditions  than  the 
cells  already  established,  and  were  unable,  in  consequence,  to  com- 
pete with  them.  He  thus  saw  in  the  rarity  of  natural  metastases  in 
the  mouse,  no  less  than  in  the  failure  of  secondary  inoculations, 
an  indication  of  the  existence  of  a  type  of  athrepsia  different  from  that 
naturally  occurring  in  the  rat.  Entirely  in  accord  with  the  hypothe- 
sis thus  outlined  could  be  arranged  his  observation  that  with  very 
slowly  growing  tumors  like  chondromata,  a  second  inoculation  was 
occasionally  successful,  since  the  more  slowly  the  first  tumor  grew  the 
less  nourishment  need  it  assimilate,  and  the  more  favorable  would  be 
the  conditions  for  cells  subsequently  introduced. 

The  absence  of  macroscopic  metastases  was  accordingly  not  an  in- 
dication against  the  malignant  character  of  a  tumor,  but  rather  the 
expression  of  a  special  type  of  malignancy  resulting  from  an  enormous 
energy  of  growth. 

A  partial  confirmation  of  Ehrlich's  hypothesis  seemed  to  have  been 
afforded  by  some  experiments  of  Schone,^  who  argued  that  if  it  were 
tenable  every  obstacle  to  the  growth  of  a  second  tumor  should  be  re- 
moved by  the  extirpation  of  the  first.  This  assumption  was  put  to 
the  test  in  a  fairly  large  number  of  experiments,  with  the  result  that 
a  secondary  inoculation  done  after  the  expiration  of  from  eight  days 

1  Verhandl.  d.  deutschen  Gesellsch.  f.  Chir.,  1907,  xxxvi,  213. 
Deut.  med.  Woch.,  1907,  xxxiii,  866. 


l62  RESISTANCE 

to  three  weeks,  when  the  operation  wound  had  healed,  was  successful 
in  as  large  a  percentage  as  in  normal  animals. 

Gierke  ^  thought,  however,  that  the  experiment  did  not  necessarily 
prove  the  mere  disappearance  of  the  influence  of  the  tumor  to  have 
effected  this  revolution  in  the  organism  of  the  mouse.  If,  as  he  him- 
self thought,  the  negative  result  of  secondary  inoculation  in  tumor- 
bearing  animals  was  due  not  to  athrepsia,  but  to  acquired  resistance 
ehcited  by  the  introduction  and  partial  absorption  of  a  large  dose  of 
tumor  at  the  time  of  the  first  inoculation,  it  would  be  possible  to  ex- 
plain Schone's  facts  by  the  assumption  that  resistance  could  be  abro- 
gated by  drastic  operation  —  an  explanation  which  Schone  himself 
had  not  failed  to  consider. 

A  result  exactly  opposite  to  Schone 's  was  the  outcome  of  experi- 
ments by  Uhlenhuth,  Haendel,  and  Steffenhagen,-  who  demonstrated 
that  rats  suddenly  freed  by  operation  of  large  tumors  averaging 
about  three  weeks  in  age,  were  resistant  to  immediate  or  later  re- 
inoculation,  if  the  growth  had  been  so  thoroughly  removed  that  no 
recurrence  took  place.  In  animals  with  recurrent  timiors  (and  Uhlen- 
huth and  his  colleagues  noted  in  passing  that  such  tumors  were  dis- 
tinguished by  particularly  energetic  growth)  re-inoculation,  on  the 
contrary,  was  always  successful.  This  observation  they  could  not 
accord  with  Ehrlich's  hypothesis  of  athrepsia,  nor  could  they  coordi- 
nate with  that  hypothesis  the  particularly  favorable  results  following 
simultaneous  inoculation  of  rats  at  several  sites.  Moreover,  they  found 
that  tumors  secondarily  inoculated  usually  grew  in  those  animals  in 
which  the  first  tumor  was  flourishing,  while,  on  the  other  hand,  in  rats 
where  the  first  tumor  was  backward  in  growth  and  showed  an  inclina- 
tion toward  necrosis  and  regression,  re-inoculation  was  unsuccessful. 

The  results  of  their  experiments  the  authors  explained  as  follows  :  — 

After  the  implantation  of  a  tumor  there  followed  a  confhct  between 
its  cells  and  the  animal's  body.  This  struggle  did  not  stop,  even 
though  the  growth  estabhshed  itself,  but  became,  on  the  contrary,  more 
intense,  and  there  still  remained  the  chance  that  the  organism  might 

1  Beitr.  zur  path.  Anat.,  etc.,  (Ziegler),  1908,  xliii,  352. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  143. 

2  Centralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Ref.,  1910,  xlvii,  Beiheft,  158. 
Zeitschrift  f.  Immunitdtsforsch.,  etc.,  Orig.,  1910,  vi,  657. 

Arb.  a.  d.  Kaiserl.  Gesundheitsamte,  191 1,  xxxvi,  498. 


RESISTANCE  163 

finally  conquer.  When  the  host  was  victorious  there  ensued  cessation 
of  growth  on  the  part  of  the  tumor,  necrosis,  and  finally  complete 
disappearance,  and  the  protective  stuffs  remaining  after  destruction  or 
complete  ablation  of  a  neoplasm  were  able  to  prevent  the  development 
of  mahgnant  cells  subsequently  inoculated ;  the  animals  were  immune. 
But  the  tumor  cells  themselves  had  time,  during  the  strife,  to  attain 
some  degree  of  resistance  toward  the  antistuffs  of  the  organism,  so 
that  elements  left  behind  at  operation  were  serum  proof,  and  were, 
moreover,  under  more  favorable  conditions  for  obtaining  nourishment 
than  they  had  been  formerly  in  the  presence  of  a  large  tumor.  Hence, 
the  cells  of  recurrences  were  significant  for  their  very  powerful  growth 
energy;  and  as  they  were  able  not  only  to  make  their  way  against 
antistuffs,  but  even  to  paralyze  these  bodies,  there  was  no  bar  to  re- 
inoculation  in  an  animal  with  a  recurrent  tumor.  That,  in  the  absence 
of  recurrence,  re-inoculation  even  with  the  original  serum  proof  tumor 
was  negative,  could  be  explained  on  the  supposition  that  the  action  of 
the  protective  bodies  was  concentrated  on  the  new  graft,  which  had  been 
so  disturbed  in  its  growth  by  removal  to  another  part  of  the  body  that 
it  succumbed  to  their  attack. 

The  work  of  these  authors  has  been  criticized  by  Russell  ^  on  the 
ground  that  incomplete  excision  was  not  the  factor  which  determined 
whether  re-inoculation  would  or  would  not  be  successful.  This  was 
decided  solely  by  the  reaction  taking  place  between  the  animal  and 
the  growth  first  implanted.  Furthermore,  the  assumption  of  an 
alteration  in  the  tumor  parenchyma,  by  virtue  of  which  it  became 
resistant  to  immunity,  accorded  but  ill  with  Russell's  experience, 
for  attempts  to  obtain  such  refractory  neoplasms  by  cultivating  those 
tumors  which  had  grown  as  an  exception  in  mice  immunized  with 
embryo  skin  had  not  produced  a  growth  resistant  to  the  forces  of  im- 
munity called  into  play  by  embryo  skin. 

The  deductions  drawn  by  Uhlenhuth  and  his  colleagues  were  refuted 
also  by  Apolant,^  who  saw  in  the  experiments  a  substantiation  rather 
than  a  contradiction  of  Ehrlich's  views.  In  the  first  place,  the  rapid 
growth  of  recurrences  could  not  be  explained  by  assuming  that  their 
cells  were  serum  proof,  for  the  fact  that  re-inoculation  with  the  same 

^ Fifth  Set.  Report,  Imperial  Cancer  Research  Amt/,. London,  191 2,  16. 
^  Zeitschrift  f.  Immunitatsjorsch.,  etc.,  Orig.,  1911,  x,  103. 


164  RESISTANCE 

tumor  was  fruitless  stood  in  direct  contradiction  to  such  an  assumption. 
The  authors'  explanation  of  this  discrepancy  Apolant  could  not 
admit,  for  if  the  cells  were  serum  proof  they  would  be  able  to  resist  the 
attacks  of  antistuffs.  As  for  the  dislocation  of  tumor  cells  from  their 
original  position,  while  it  was  no  doubt  true  that  they  suffered  injury 
during  the  process,  still  it  was  the  very  method  by  which  successful 
tumor  transplantation  had  been  effected  over  a  period  of  ten  years. 
Apolant  could  conceive  of  no  more  striking  proof  of  Ehrhch's  views 
than  the  rapid  growth  of  recurrences,  for  the  same  quantity  of  specific 
nutrient  material  which,  before  the  operation,  had  to  suffice  for  the 
whole  tumor,  was  now  at  the  disposal  of  a  relatively  small  number  of 
cells,  and  their  more  rapid  proHferation  was,  therefore,  readily  compre- 
hensible. 

When  Uhlenhuth  and  his  associates  asserted  that  the  result  of  double 
and  triple  inoculations  was  not  in  accord  with  the  hypothesis  of  athrep- 
sia,  they  had  overlooked  Ehrhch's  condition  that  the  presence  of  a 
rapidly  growing  tumor  was  essential  for  the  supervention  of  athreptic 
immunity. 

Although  the  authors  under  discussion  had  found  that  the  yield 
from  re-inoculation  of  operated  rats  depended  entirely  upon  whether 
the  first  growth  had  or  had  not  been  radically  removed,  Apolant 
could  find  no  evidence  that  the  outcome  of  the  second  inoculation  was 
dependent  upon  the  appearance  or  non-appearance  of  recurrences,  for 
in  about  20%  of  the  rats  and  15%  of  the  mice  there  were  striking  ex- 
ceptions to  Uhlenhuth's  results.  It  was  a  question  whether  all  the 
cases  that  remained  free  from  recurrence  had  really  been  subjected 
to  complete  operation.  During  the  radical  excision  of  large  growths 
extensive  defects  ensued,  to  heal  only  with  difficulty  and  under  great 
tension,  and  the  nourishment  of  tiny  fragments  remaining  would  there- 
fore be  seriously  impaired  by  the  tightly  stretched  skin,  their  cells 
undergoing  necrosis  and  absorption,  although  larger  pieces  with  better 
circulatory  connections  might  be  able  to  continue  growth.  In  the 
former  case  active  resistance  would  supervene  from  the  absorption  of 
tumor  remnants,  while  in  the  latter  there  would  be  no  absorption  and 
consequently  no  resistance. 

•  Clowes  ^  found  that  if  mice  already  developing  growths  were  inocu- 

1  British  Med.  Joiir.,  1906,  ii,  1551. 


RESISTANCE  165 

lated  a  second  time  from  five  to  ten  days  after  the  first  implantation, 
tumors  were  rarely  produced,  or,  if  produced,  grew  far  more  slowly 
than  in  normal  controls.  Less  than  6  %  of  tumors  resulted  from  such 
secondary  inoculations,  while  in  the  normal  controls  the  yield  was 
95%-  While  thus  agreeing  with  Ehrlich  so  far  as  observation  went, 
Clowes  could  not  subscribe  to  his  hypothesis,  and  explained  the 
failure  of  the  second  graft  by  the  assumption  of  immune  forces  in- 
duced in  the  serum  as  the  result  of  a  reaction  against  the  developing 
tumor. 

Investigating  athreptic  immunity,  Hertwig  and  PolP  determined 
that  a  growth  already  present,  whether  small  or  large,  extended  no  pro- 
tection against  the  development  of  new  tumors  when,  at  the  expiration 
of  varying  periods,  second,  or  even  third  inoculations  were  performed  ; 
nor  could  they  discover  any  restrictive  influence  upon  the  younger 
through  the  deprivation  of  nourishment.  In  many  cases,  indeed,  the 
nodules  were  of  similar  proliferative  energy,  and  those  secondarily 
inoculated  not  seldom  outstripped  neoplasms  already  established. 
The  tumor  with  which  they  were  working,  even  though  it  were  not  of 
such  vigorous  growth  as  that  used  by  Ehrlich,  might  still  be  fairly 
classed  among  the  rapidly  growing,  for  after  two  or  three  months  it 
reached,  in  many  of  their  mice,  a  weight  equal  to  that  of  the  animal 
bearing  it. 

Lewin,^  who  worked  with  both  rat  and  mouse  tumors  of  rapid 
growth,  expressed  his  entire  agreement  with  the  findings  of  Hertwig 
and  Poll,  for  he  had  never  failed  successfully  to  re-inoculate  tumor- 
bearing  animals. 

Borrel,^  repeating  Ehrlich's  experiments,  achieved  the  same  result 
at  which  Ehrhch  had  arrived,  when  tumor  emulsion  was  inoculated  after 
the  manner  practised  at  the  Frankfort  laboratory,  although  when 
intact  fragments  were  ingrafted  a  contradictory  outcome  was  obtained. 
When  the  site  of  the  inoculation  of  an  emulsion  was  examined  microscop- 
ically, it  could  be  shown  that  only  apart  of  the  introduced  materia]  had 
proliferated.     The  remainder,  having  been  absorbed,  might  have  given 

^  Ahhandl.  d.  Konigl.  Preuss.  Akad.  d.  Wissensch.,  1907,  31. 
^  Berl.  kiln.  Woch.,  1907,  xliv,  1606. 

Zeitschrift.  f.  Krebsforsch.,  1907-1908,  vi,  307. 
*  Bidl.  de  rinst.  Past.,  1907,  v,  594. 


1 66  RESISTANCE 

rise  to  cytolytic  antibodies  able  to  embarrass  the  development  of  cells 
deposited  at  a  second  inoculation.  The  cells  first  introduced  were  not 
affected  by  these  hypothetical  antibodies  because  time  was  required 
for  their  elaboration  and  they  were,  therefore,  unable  to  exert  injury 
upon  a  tumor  in  which  growth  had  been  already  inaugurated.  But 
such  antibodies  might  prevent  the  development  of  cells  subsequently 
inoculated,  by  being  present  at  a  time  when  vascular  connection  had 
not  yet  been  estabHshed. 

Contrasted  with  this  first  condition  was  the  second  where,  an  entire 
fragment  ha\dng  been  inoculated,  no  absorption  took  place  in  the 
majority  of  cases.  In  such  an  event,  re-inoculation  performed  after 
an  interval  of  from  eight  to  twenty-one  days,  at  a  time  when  the  first 
tumor  had  already  advanced  to  a  large  size,  was  entirely  successful. 

Bridre^  also  was  unable  to  substantiate  EhrHch's  observations,  find- 
ing, on  the  contrary,  that  mice  already  bearing  a  tumor  offered  a  favor- 
able soil  for  a  second,  whether  this  were  of  the  same  or  of  a  different  type. 
Indeed,  in  certain  experiments,  mice  in  which  tumor  "B"  was  already 
estabhshed  could  be  re-inoculated  with  this  growth  in  ioo%  of  cases^ 
while  the  controls  did  not  furnish  more  than  80%.  Although  the 
proportion  of  successful  inoculations  was  not  always  thus  increased, 
tumor-bearing  mice  were  at  least  as  susceptible  to  re-inoculation  as 
normal  animals.  The  results  of  Bridre's  inoculations  were  not  due 
to  the  low  virulence  of  the  tumor  first  implanted,  and  he  explained 
the  discrepancy  between  his  results  and  Ehrlich's  by  the  difference  in 
the  amounts  of  tumor  inoculated. 

The  experiments  of  Borrel  having  been  repeated  in  Ehrlich's  labora- 
tory, Apolant-  contended  that  athrepsia  was  readily  demonstrable 
after  the  inoculation  of  tumor  fragments,  its  presence  being  indicated 
in  such  a  case  by  the  much  smaller  weight  of  the  secondary  tumors  as 
contrasted  with  those  in  the  controls. 

MichaeHs^  could  not  see  that  the  presence  of  one  growth  prevented 
re-inoculation  of  a  second,  but  suggested  that  his  failure  might  have 
been  due  to  absence  in  his  own  tumor  of  the  extreme  prohferative 
power  possessed  by  that  of  Ehrlich. 

^  Ann.  de  I'Insf.  Past.,  1907,  xxi,  771. 

^  Zeitschrift  f.  Immiinitdtsforsch.,  etc.,  Orig.,  1911,  x,  104. 

^  Zeitschrift  f.  Krehsforsch.,  1907,  v,  195. 


RESISTANCE  167 

Bashford  and  Murray^  had  written  two  years  before  the  publication 
of  Ehriich's  hypothesis  "...  that  transplantation  can  be  successfully 
performed  in  animals  in  which  tumours  have  already  developed  four- 
teen days  to  ten  weeks  after  the  first  effective  transplantation,  i.e. 
both  when  the  primary  tumour  is  small,  and  when  it  has  attained  a 
large  size."  Subsequent  experiments  gave  them  no  reason  to  retract 
this  statement,  and  after  four  years  of  further  experience,  in  a  paper 
published  with  Haaland,  they^  stated  that  a  series  of  inoculations  into 
tumor-bearing  animals  confirmed  what  had  previously  been  said .  While 
in  experiments  with  rapidly  growing  tumors  they  did  encounter  the 
phenomenon  described  by  Ehrlich,  they  believed  that  the  result  of 
a  secondary  inoculation  was  determined,  not  by  the  growth  rate  of  the 
tumor  already  established,  but  by  the  size  of  the  dose  primarily  inocu- 
lated. Mice  in  which  the  first  tumor  had  developed  from  a  small 
quantity  were  re-inoculated  with  large  or  small  amounts,  and  con- 
versely, the  same  manner  of  re-inoculation  was  practised  on  mice 
whose  primary  tumor  had  developed  from  a  large  dose.  The  results  in 
both  series  were  entirely  in  accord  and  led  the  authors  to  express  the 
conviction  that  concomitant  immunization,  evolved  by  the  absorp- 
tion of  tumor  at  the  time  of  the  first  inoculation,  was  the  most 
natural  explanation  of  the  facts,  and  that  the  athreptic  explana- 
tion was  inadequate.  A  negative  result  on  re-inoculation  was  thus 
''.  .  .  due  to  a  secondary  change  in  the  positive  animal  follow- 
ing on  the  absorption  of  tumour  material.  The  quantitative 
relations  obtaining  between  the  tumour  tissue  introduced  and 
the  degree  of  protection  resulting,  demonstrate,  just  as  effectually 
in  the  case  of  animals  bearing  tumours  as  in  the  case  of  normal 
animals,  that  we  have  here  to  deal  with  an  active  immunity." 
When  a  growth  had  reached  a  very  large  size,  re-inoculation 
into  the  animal  bearing  it  was  either  negative  or  was  followed  by 
small  stationary  tumors  only.  This  occurred,  however,  because  the 
limit  of  nutritive  capacity  in  the  animal  had  been  reached,  and 
the  authors  compared  the  issue  with  the  poor  results  obtained  after 
inoculation  of  mice  in  ill  health. 

1  Sci.  Reports,  Cancer  Research  Fund,  Lorxdon,  1904,  No.  i,  15. 

2  Third  Sci.  Report,  Imperial  Cancer  Research  Fund-  London,  1908,  386. 
Zeitschrift  f.  Imnmnitatsforsch.,  etc.,  Orig.,  1909,  i,  519. 


l68  RESISTANCE 

Gierke.^  working  in  the  same  laboratory,  concluded  from  extensive 
experiments  that  " " .  .  .a  mouse  with  a  tumour  oilers  conditions  far  more 
favourable  to  subsequent  inoculations  than  those  obtaining  in  normal 
mice."  There  were  two  possible  explanations  for  this  fact.  "Either 
these  animals  have  been  picked  out  by  the  primary  inoculation,  which 
are  naturaUy  suitable  for  tumour  implantation,  and.  therefore,  they 
are  susceptible  also  to  a  second  inoculation,  or.  the  suitabiHty  for  im- 
plantation is  increased  in  certain  cases  by  the  primary  gro^\dng  tumour." 
He  himseh"  inchned  to  choose  the  second  explanation,  although  realizing 
that  the  experiments  did  not  afford  an  absolute  demonstration  of  its 
vahdity.  The  contrast  between  these  results  and  Ehrlich's.  as  it  was 
probably  not  due  to  variations  in  material.  Gierke  ascribed  to  dissimilari- 
ties in  technic.  and  particularly  to  differences  in  dose.  Such  large 
amounts  as  had  been  employed  in  Ehrhch's  laboratory  were  in  great 
part  absorbed,  only  a  comparatively  small  number  of  the  cells  taking 
part  in  the  formation  of  the  new  growth,  and  the  absorption  of  such  a 
large  amount  of  tumor  would  increase  resistance  toward  a  second  graft. 

Jobling,-  without  \^dshing  to  discuss  Ehrhch's  \dews,  offered  the  re- 
sults of  secondary  and  tertiar}-  inoculations  ^^dth  the  slowly  growing 
Flexner- Job  ling  rat  adeno- carcinoma.  His  experiments  showed,  in 
brief,  that  a  prohferating  tumor  did  not  prevent  the  successful  implan- 
tation of  another  of  the  same  kind,  although  the  secondary  inoculations 
were  likely  to  ^deld  a  smaller  number  of  growing  nodules  than  the 
first.  In  rats  with  stationary  or  receding  growths,  however,  re-inoc-. 
ulation  usually  failed. 

The  athreptic  h\'pothesis  has  been  subjected  by  Bashford  and 
Russell ''  to  a  criticism  even  more  searching  than  any  so  far  described, 
and  based  upon  the  microscopic  examination  of  the  re-inoculation 
site  at  successive  inter^-als. 

Study  of  young  grafts  had  already  demonstrated  that  the  tumor 
cells  continued  to  prohferate,  that  the  stroma  died  and  was  replaced 
by  one  furnished  from  the  new  host,  and  that  in  mice  resistant  to 

1  Beitr.  zur  path.  An-at.,  etc.,  fZiegler),  1908,  xliii,  347. 

Third  Sci.  Report,  ImperM  Cancer  Research  Fund,  London,  1908,  137,  139. 
^Monographs  on  Medical  and  Allied  Subjects,  Rockefeller  Institute,  New  York,  1910, 
No.  I,  57- 

^  Proc.  Roy.  Soc,  Series  B,  1909-1910,  bccdi,  298. 
Lancet,  1910,  i,  782. 


RESISTANCE  169 

carcinoma  there  was  a  failure  to  supply  this  specific  scaffolding,  whether 
immunity  had  been  induced  by  the  pre\dous  absorption  of  tumor  or  of 
normal  tissue. 

It  was  found  that  re-inoculation  failed  except  in  those  mice  in 
which  the  first  tumor  had  continued  to  grow  rapidly.  When  growth 
had  slackened,  or  when  absorption  had  begun,  no  tumor  developed  from 
secondary  inoculation ;  or,  in  other  words,  the  better  the  growth  of  the 
first  tumor,  the  more  favorable  were  the  chances  that  a  second  im- 
plantation would  be  successful. 

At  the  site  of  the  re- inoculation  there  was  an  inhibition  of  the  stroma 
reaction  in  those  mice  in  which  the  primary  tumor  had  become  slower 
of  growth  or  had  begun  to  decrease  in  size,  and  it  was  thus  demonstrated 
beyond  reasonable  doubt  that  the  actual  mechanism  in  play  was  the 
induction  of  a  resistance  identical  with  that  aheady  described  in  other 
refractory  animals.  The  successful  re-inoculation  of  mice  bearing  the 
most  rapidly  growing  tumors  was  readily  understandable  on  this  basis, 
for  the  absorption  of  tumor  tissue  was  here  almost  niU  and  resistance 
had,  therefore,  not  been  estabhshed.  The  authors  concluded  that  to 
assume  the  presence  of  a  special,  or  athreptic,  immunity  in  tumor- 
bearing  animals  would  be  superfluous. 

EhrHch's  ^  reply  to  his  earHer  critics  was  an  emphasis  of  his  former 
statements,  that  in  order  for  the  phenomenon  of  athreptic  immunity 
to  be  brought  out  the  preHminary  inoculation  must  have  been  made 
with  a  tumor  strain  of  maximal  virulence,  and  that  retardation  of 
growth  was  just  as  much  an  evidence  of  athrepsia  as  it  was,  in  active 
resistance,  an  e\"idence  of  partial  immunization.  The  conception 
tumor  virulence  embraced  two  quahties  not  always  separable  from  one 
another,  namely,  proliferative  energy,  measured  by  the  rapidity  of 
growth,  and  trans plantability ,  evaluated  by  the  percentage  of  success- 
ful inoculations.  WTiile  these  two  quahties  generally  went  hand  in 
hand,  exceptions  occurred  now  and  again,  the  most  important  being  a 
chondroma  which,  in  spite  of  its  feeble  growth  energy,  could  be 
successfully  transferred  in  100%  of  cases.  As  regarded  transmissi- 
bility,  a  limit  was  naturally  imposed  upon  the  increase  of  \'irulence  at 
100%,  while  for  the  augmentation  of  growth  energy  the  hmit  varied 
with  the  different  strains.     Lowest  mth  chondroma,  higher  —  although 

^  Verttaiidl.  d.  deutscheti  path.  Gesellsch.,  1908,  12'^  Tagung,  14. 


lyo  RESISTANCE 

very  variable  —  with  carcinoma,  it  reached  its  maximum  in  the  sar- 
comata, among  which  tumors  could  be  obtained  that  in  three  or  four 
weeks  might  equal  the  size  of  the  animal  itself. 

Ehrlich  expressed  the  conviction  that  over  and  above  characteristics 
so  obvious  as  inoculation  percentage  and  rapidity  of  growth,  there  were 
other  and  more  latent  qualities  to  be  interpolated  in  the  conception  of 
virulence.  Thus  he  had  observed  that  two  strains  of  carcinoma,  al- 
though they  were  about  equal  in  inoculation  percentage  and  growth 
energy,  varied  in  the  power  to  prevent  successful  re-inoculation, 
one  entirely  excluding  it,  the  other  limiting  it  only  to  a  slight  extent. 
The  factor  distinguishing  the  former  he  provisionally  described  as 
exhaustive  or  ereptive,  but  left  open  the  question  whether  or  not  it  rested 
upon  a  maximum  avidity  of  the  tumor  cells  or  upon  some  specific 
relationship  toward  the  materials  necessary  for  tumor  growth.  The 
expression  maximal  virulence  he  preferred  to  restrict  to  such  tumors 
as  had  all  three  qualities  developed  in  the  highest  degree,  and  in  which 
they  persisted  without  variation. 

Criticizing  Borrel's  comparison  of  the  results  following  the  inocula- 
tion of  emulsion  and  intact  grafts  respectively,  Ehrlich  replied  that 
in  his  own  experience  tumors  had  always  exhibited  a  more  rapid  growth 
after  having  been  introduced  in  the  form  of  an  emulsion  —  a  fact  that 
harmonized  but  poorly  with  any  supposition  implicating  antibodies. 
Accepting  for  the  moment,  with  Borrel,  the  assumption  that  antibodies 
were  always  elaborated  in  great  quantity  after  the  inoculation  of 
an  emulsion,  it  was  difficult  to  understand  why  they  did  not  hinder 
the  growth  of  the  first  tumor.  It  was  certain  that  a  nodule  already 
established  and,  therefore,  well  vascularized,  would  be  subjected  to  a 
much  greater  chance  of  contact  with  antibodies  circulating  in  the  blood 
than  would  one  newly  introduced  under  the  skin,  although  it  could, 
of  course,  be  objected  that  the  proliferating  tumor  had  become  proof 
against  the  new-formed  antibodies.  However,  all  the  re-inoculations 
at  the  Pasteur  Institute  had  been  made  with  growths  which,  having 
survived  many  generations  of  emulsion  inoculation,  were  serum  proof 
to  the  same  degree  as  the  tumor  already  present ;  and  as  there  was  no 
ground  for  ascribing  to  either  neoplasm  differences  in  the  grade  of 
resistance,  Borrel's  explanation  was  untenable. 

Nevertheless,  his  experiments  had  been  repeated,  with  the  result 


RESISTANCE  171 

that  athrepsia  had  been  demonstrable  even  after  the  insertion  of 
tumor  fragments,  although,  to  be  sure,  the  same  grade  had  not  been 
reached  as  might  have  been  attained  after  introduction  of  an  emulsion. 
The  explanation,  however,  was  quite  opposite  to  Borrel's.  As  growth 
in  tumors  resulting  from  the  implantation  of  intact  grafts  was  appre- 
ciably slower  than  in  those  following  the  inoculation  of  an  emulsion, 
there  was  absent  in  the  former  case  that  most  important  element  in 
the  production  of  athreptic  immunity  —  rapid  proliferation. 

Direct  proof  of  the  existence  of  athreptic  immunity  had  been  afforded 
further  by  the  transplantation  of  artificial  tumor  mixtures,  already 
described  in  detail  by  Apolant.^  Several  years  before  the  publication 
of  Ehrlich's  present  article,  the  prompt  development  of  a  mixed  tumor 
would  follow  the  inoculation  of  a  mixture  of  one  of  their  sarcomata 
with  a  carcinoma.  But  repeated  at  the  time  of  writing,  when  the  vir- 
ulence relationship  of  the  two  strains  had  altered  in  favor  of  the  former, 
the  same  experiment  would  yield  a  pure  sarcoma.  However,  by  the  ac- 
tion of  extreme  cold  the  virulence  of  the  sarcoma  could  be  diminished 
to  a  point  where  it  was  again  equal  to  that  of  the  carcinoma,  so  that  a 
mixed  tumor  would  ensue  upon  injection  of  a  mixed  emulsion.  When 
the  virulence  of  the  sarcoma  was  still  more  reduced,  a  pure  carcinoma 
could  be  obtained  from  the  mixture.  These  results  demonstrated  that 
Apolant  had  been  dealing  with  an  overgrowth  by  the  stronger  com- 
ponent or,  in  other  words,  by  the  one  which  more  strongly  attracted 
the  nutriment  to  itself.  The  action  of  antibodies  did  not  in  any  way 
enter  into  the  discussion. 

If,  now,  it  were  imagined  that  a  highly  virulent  sarcoma  and  a  car- 
cinoma of  lower  virulence,  instead  of  being  mixed,  had  been  inoculated 
separately  at  two  different  sites,  no  essential  change  in  the  athreptic 
influences  would  have  been  brought  about,  and  the  explanation  of 
the  development  of  the  more  vigorous  tumor  only  would  offer  no 
difficulty. 

With  these  reflections  as  a  basis,  EhrKch  sought  to  define  clearly  the 
presence  of  athreptic  influences  by  making  primary  and  secondary 
inoculations,  not  with  the  same  tumor,  but  with  tumors  differing  in 
histology  as  well  as  in  virulence.  In  the  first  two  experiments  the 
preliminary  inoculation  was  done  with  a  sarcoma,  re-inoculation  with 

^  ZeUschrifl  f.  Krebsforsch.,  1907-1908,  vi,  251. 


172  RESISTAXCE 

a  carcinoma  of  weaker  Airulence  folloA\T.ng  nine  or  fourteen  days  after- 
ward. It  was  found  that  in  the  series  re-inoculated  after  fourteen  days 
not  a  single  carcinoma  had  grov^-n.  while  in  the  nine-day  series  only  two 
insignificant  tumors  occurred  among  eighteen  inoculations.  Controls 
in  both  cases  showed  a  large  number  of  .growths.  "When  the  experi- 
ment was  reversed  and  the  tumor  of  lovrer  \drulence  was  inoculated 
first,  to  be  follovred  nine  days  later  by  the  more  \drulent  growth,  there 
v\-as  found  but  slight  cKnerence  in  size  between  the  sarcomata  in  normal 
mice  and  those  that  had  been  inoculated  into  animals  already  bearing 
carcinomata.  although  there  was  considerable  disparity  between  these 
carcinoniata  and  those  in  normal  mice.  Thus  it  was  e\ddent  that  a" 
tumor  of  low  \-irulence  hindered  only  to  a  shght  degree  the  growth  of  a 
more  -virulent  one  inoculated  afterward  and.  moreover,  that  it  was 
considerably  impeded  in  growth,  even  in  spite  of  its  greater  age,  by 
the  more  \-irulent  neoplasm  subsequently  ingrafted.  The  experiment 
demonstrated  in  a  sahent  way  the  signiiicance  of  athreptic  influences, 
and  was  entirely  analogous  to  Apolant's  inoculations  of  tumor  mix- 
tures, for  in  both  cases  the  development  of  different  growths  in  the 
same  animal  was  dependent  upon  the  respective  virulences  of  these 
grafts  or.  in  other  words,  upon  the  a\dchty  of  their  cells  for  nutriment. 

In  order  to  prove  the  principle  of  athrepsia  it  was  sufficient  to  show 
?jv  a  series  of  trustworthy  experiments  that  one  grov,-ing  tumor  was 
able  to  exert  an  adverse  iniiuence  upon  the  growth  of  another,  for  a 
retardation  of  proKferation  vras  the  expression  of  a  partial  immunity. 

Ehrhch  concluded  this  article  with  the  imphcation  that  the  negative 
result  attendant  upon  the  inoculation  of  pregnant  animals,  or  the  slow 
growth  of  such  tumors  as  cHd  occur,  was  added  evidence  in  favor  of  the 
h\-pothesis  of  athrepsia. 

V.  Dungern  and  Coca  ^  considered  that  immunity  to  the  trans- 
plantation of  tumors  was  a  condition  of  allergie.  In  5tud\ing  a  hare 
sarcoma  that  was  transmissible  to  rabbits,  they  fotmd  that  while  there 
developed  only  a  sHght  circumscribed  thickening  about  a  first  graft  in 
the  rabbit,  a  second  one  educed  a  much  stronger  reaction,  in  the  shape 
of  a  more  or  less  severe  indammatory  swelling.  The  response  was 
weU  marked  by  the  end  of  tv\-enty-four  hours,  still  clear  after  two  days, 
and  receded  on  the  third  day.  Thus  there  appeared  phenomena  around 
^  Zeitschrift  f.  Immunitdtsforsch.,  etc.,  Orig.,  1909,  ii,  391. 


RESISTANCE 


173 


the  second  Implantation  of  foreign  sarcomatous  tissue  which  might  be 
described  as  a  local  reaction  of  h}'persusceptibility. 

Histological  investigation  of  the  inoculation  site  in  immune  animals 
on  the  second  day  revealed,  beside  necrosis,  the  presence  of  a  great 
number  of  macrophages  in  the  tissues,  capillaries,  and  small  veins, 
while  in  normal  rabbits,  on  the  contrary,  such  cells  were  of  rare  occur- 
rence. A  few  days  later  the  inoculation  site  in  immune  animals  was 
crowded  with  these  elements,  and  surrounding  the  blood  vessels 
could  be  found  great  collections  of  lymphoid  and  plasma  cells. 
The  most  striking  lesion  of  all,  however,  was  a  thrombosis  (by  masses 
of  macrophages)  of  nearly  all  the  smaller  and  larger  veins  in  the  neigh- 
borhood of  the  central  necrosis.  In  several  cases  the  authors  observed 
after  the  second  inoculation  a  softening  of  the  remains  of  the  graft 
first  introduced,  small  nodules  that  had  been  firm  for  weeks  or  months 
becoming  soft  in  a  few  days,  and  here  there  was  present  the  same  macro- 
phage reaction.  The  condition  corresponded  entirely  with  that  found 
in  tuberculous  tissue,  composed  as  it  was  of  a  central  necrotic  zone  sur- 
rounded by  endothelium-Hke  cells,  large  typical  giant  cells  with  periph- 
eral nuclei,  and  beyond  these,  lymphoid  and  plasma  cells.  Exactly 
the  same  appearances  were  to  be  seen  in  transplanted  tumors  under- 
going spontaneous  absorption,  as  well  as  in  the  lymph  nodes  in  cases 
where  a  tumor  of  particularly  vigorous  growth  had  reached  a  consider- 
able size.     The  lesion  was  distinct,  also,  in  hares. 

This  reaction,  which  v.  Dungern  and  Coca  considered  significant 
for  the  elucidation  of  tumor  immunity,  they  correlated  with  hypersus- 
ceptibility.  Upon  the  first  inoculation  foreign  protoplasmic  sub- 
stances, in  the  form  of  tumor  cells,  entered  the  circulation  and  were 
taken  up  by  the  macrophages jor  their  mother  cells,  producing  a  con- 
dition of  sensitiveness  in  these  elements  which,  therefore,  reacted  more 
quickly  and  more  strongly  when,  at  a  second  inoculation,  the  identical 
foreign  protoplasm  was  again  encountered.  The  specific  stimulus 
might  act  either  by  chemotaxis  or  by  stimulating  the  development  of 
macrophages  from  other  cells.  Observation  spoke  more  strongly  for 
the  second  possibihty,  for  when  the  reaction  was  pronounced  there  was 
always  an  unmistakable  growth  of  the  vascular  endothehum  coupled 
with  the  appearance  of  many  karyokinetic  figures,  while  in  contradis- 
tinction to   this  there  was  no  evidence  of  endotheHal   proliferation 


174  RESISTANCE 

in  the  absence  of  the  macrophage  reaction.  The  lesion,  while  generally 
very  marked  in  the  case  of  transplanted  tumors,  was  not  so  distinct 
where  primary  growths  were  concerned. 

To  see  if  it  were  possible  to  find  any  constant  differences  between 
fragments  of  tumor  implanted  into  normal  mice  and  those  which  had 
been  introduced  into  resistant  animals,  RusselP  subjected  the  grafts  to  a 
systematic  examination.  The  material  was  obtained  by  the  removal  of 
small  implantations  six,  twelve,  twenty- four,  etc.,  hours  after  their 
inoculation.  The  phenomena  during  the  first  two  days  were  the 
same  in  both  series  of  mice,  but  after  this  period  it  was,  as  a  rule, 
easily  possible  to  distinguish  between  grafts  from  resistant  and  those 
from  normal  animals.  In  a  refractory  mouse  the  processes  occurring 
on  and  after  the  third  day  were  as  follows :  — 

"The  necrosis  in  the  center  of  the  graft  extends,  until  all  the  graft 
has  degenerated  with  the  exception  of  the  epithelial  cells  in  the  im- 
mediate neighborhood  of  the  host  tissues ;  the  fibrinous  exudate 
becomes  absorbed  and  the  number  of  polymorphonuclear  leucocytes 
decreases.  The  acinous  arrangement  is  destroyed,  and  the  turnour  cells 
lie  as  a  single  layer  of  cells  between  the  necrotic  center  of  the  graft 
and  the  host  tissues.  There  is  not  the  active  proliferation  of  the  host 
fibroblasts  seen  normally,  nor  is  there  any  development  of  new  capilla- 
ries.    The  epithelial  cells  still  continue  to  divide  mitotically. 

"As  shrinkage  of  the  necrotic  center  of  the  graft  occurs,  there  is 
produced  a  cleft  between  the  graft  and  the  host  tissues,  and  the  epithe- 
lial cells  spread  themselves  out  over  this  free  surface,  producing  a 
cystic  cavity.  .  .  . 

"The  line  of  contact  between  the  host  cells  and  the  pedicle  of  this 
dead  material  does  not  show  anything  comparable  to  the  rich  develop- 
ment of  new  tissues  seen  in  ...  a  normal  graft  at  four  days.  When  one 
examines  the  outer  wall  of  this  space  with  a  high  power,  the  lining 
membrane  is  seen  to  be  composed  of  a  layer  of  columnar  epithelium, 
one  or  more  cells  deep  and  sharply  demarcated,  as  if  by  a  basement 
membrane,  from  the  host  tissues.  The  cells  still  exhibit  mitoses,  but 
not  in  the  number  customary  in  a  growing  graft. 

"The  host  tissues  themselves  are  more  cellular  than  the  normal 
areolar  tissue  of  the  mouse,  but  this  is  mainly  due  to  the  presence  of 
^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  341. 


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RESISTANCE 


175 


polyblast  cells  and  polymorphonuclear  leucoctyes.  There  is  no  evident 
increase  in  the  vascularity  of  the  tissues.  The  absorption  of  the  ne- 
crotic mass  takes  place  very  slowly,  only  after  about  seven  days  do  the 
fibroblasts  and  polyblasts  penetrate  into  it  in  any  number,  and  about 
12  to  14  days  is  necessary  for  the  whole  to  be  cleared  up." 

The  outstanding  feature  in  refractory  animals  was  thus  the  failure 
to  supply  a  vascular  stroma. 

The  absence  of  the  stroma  reaction  in  resistant  animals  having  been 
demonstrated,  Russell  sought  to  explain  the  reason  for  it,  and  suggested 
that  it  might  be  ascribed  to  one  of  two  factors. 

"...  either  the  tissues  of  the  animal  have  been  altered  in  such  a 
way  by  the  process  of  immunization  that  they  no  longer  react  to  the 
stimulus  of  the  cancer  cell,  or  else  the  cancer  cell  itself  becomes 
robbed  of  its  power  of  inciting  a  specific  reaction." 

The  author  was  inclined  to  believe  that  the  immunity  was  directed 
against  the  chemotactic  influences  exerted  by  the  cancer  cell  on  the 
connective  tissues  of  the  host. 

"There  must  be  present  in  the  resistant  animals,  either  in  the 
circulating  fluids  or  in  the  tissues,  something  which  inhibits  this  chemo- 
taxis,"  although  all  attempts  to  demonstrate  in  vitro  the  presence  of  an 
active  cell  poison  had  as  yet  been  inconclusive. 

"That  the  induced  resistance  to  inoculation  is  not  due  to  a  very 
active  cell  poison  may  be  seen  from  the  power  which  the  cancer  cells 
retain,  of  continuing  their  proHferation  for  7-10  days  in  this  unfavour- 
able medium,  provided  that  they  can  obtain  sufficient  nourishment. 
Further,  the  cells  at  the  periphery  of  the  graft  are  those  which  go  on 
growing,  and  these  are  the  very  cells  which  are  most  exposed  to  the 
influence  of  any  supposed  poison,  whereas  the  cells  towards  the  centre 
of  the  graft,  which  are  not  so  exposed  to  a  free  supply  of  this  inimical 
substance,  are  the  ones  which  die  rapidly  because  of  the  interference 
with  their  food  supply." 

Russell's  observations  were  extended  by  Woglom^  to  include  an 
investigation  of  the  Flexner-Jobling  adeno-carcinoma  of  the  rat,  and 
it  was  shown  that  here,  as  in  the  mouse,  the  failure  of  grafts  to  es- 
tablish themselves  in  immune  animals  could  be  referred  to  an  absence 
of  the  specific  stroma  reaction. 

^  Fifth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  191 2,  43. 


176  RESISTANCE 

Burgess^  investigated  in  the  same  way  the  phenomenon  of  natural 
resistance  in  mice,  working  with  an  adeno-carcinoma  discoA'ered  by 
Tyzzer  in  a  Japanese  waltzing  mouse.  This  tumor  would  grow  in 
iiybrid  mice  of  the  first  generation  obtained  by  cross-breeding  Japanese 
and  common  mice,  and  in  Japanese  waltzing  mice,  but  in  all  others, 
including  the  offspring  of  hybrids  of  the  first  generation,  inoculation 
was  invariably  -unsuccessful. 

The  study  of  early  stages  showed  that  in  susceptible  Japanese 
waltzing  mice  the  tumor  receiA'ed  a  new  nbrous  and  vascular  stroma 
from  the  tissues  of  the  host.  In  non-susceptible  hybrids  of  the  second 
generation  stroma  and  blood  vessels  were  supplied  in  the  same  way, ' 
but  after  about  a  week  the  graft  became  surrounded  by  an  inflamma- 
tory exudate  which  impaired  its  nutrition.  Apparently  as  a  part  of 
this  reaction  there  occurred  in  many  of  the  non-susceptible  mice  an 
overproduction  of  fibrils  in  the  more  centrally  located  portions  of  the 
new  stroma,  but  no  such  inflammatory  process  was  seen  in  growths  of 
a  corresponding  age  in  Japanese  mice.  In  the  resistant  am'mals, 
and  probably  as  a  result  of  impaired  nutrition,  peripheral  extension 
of  the  nodule  ceased  and  central  necrosis  advanced,  until  ultimately 
the  entire  tumor  had  undergone  necrosis  and  absorption. 

In  the  case.  then,  of  animals  belonging  to  ver\- closely  related  varieties 
capable  of  interbreeding  freely,  resistance  was  only  developed  after 
several  days  of  \'igorous  growth  on  the  part  of  the  graft.  It  was  not, 
therefore,  a  result  of  the  faflure  of  the  specific  stroma  reaction  for,  in 
fact,  this  eventually  surpassed  the  response  in  susceptible  mice.  The 
active  resistance  of  the  non-susceptible  animals  was  apparently  due 
to  an  inflammaton,'  lesion  which  interfered  with  the  nutrition  of  the 
tmnor. 

AA'hile  Russell.  Woglom.  and  Burgess  had  examined  more  particularly 
the  phenomena  in  play  in  the  graft  itself,  Da  Fano  -  investigated  the 
reactions  taking  place  in  the  normal  tissues  of  the  host. 

As  hmiphocytes  appeared  in  great  number  about  inoculations  of 
immunizing  material  during  the  evolution  of  resistance,  their  relation 
to  this  condition  could  not  be  denied.     Furthermore,  their  presence 

^  Jour.  Med.  Research,  1909,  X.S.,  x\"i,  575. 
"^  Zeitschrift  f.  Itnmunitatsforsch.,  etc.,  Orig.,  1910,  v,  i. 
Fifth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1912,  57. 


RESISTANCE 


177 


was  independent  of  the  amount  of  material  inoculated.  They  were 
absent,  or  appeared  only  in  small  number  after  the  inoculation  of  dead 
tumor,  or  in  animals  already  immune.  In  growing  carcinomata  they 
were  to  be  found  only  in  places  where  local  heaHng  was  in  progress. 
The  carcinoma  cells  seemed  to  exert  some  sort  of  specific  influence  on 
the  lymphocytes,  and  the  latter  to  spread  the  resistant  state  through- 
out the  organism. 

Many  of  the  statements  referring  to  these  elements  might  be 
applied  to  the  plasma  cells,  which  Da  Fano  beheved  also  played  an 
important  role  in  the  resistant  state.  As  they  were  not  found  normally 
in  the  subcutaneous  tissue  of  the  mouse,  their  presence  in  immune 
animals  might  be  taken  to  mean  that  in  the  mechanism  of  resistance 
there  were  concerned,  beside  a  local  reaction,  changes  in  the  entire 
organism,  of  which  the  plasma  cells  were  a  morphological  expression. 


CHAPTER   VI 

HYPERSUSCEPTIBILITY 

Not  only  has  it  become  possible  to  affect  animals  in  the  direction 
of  making  them  less  susceptible  to  tumor  growth ;  the  occurrence  of 
a  modification  in  the  opposite  direction  has  been  suggested  by  several 
writers  —  a  transformation  of  the  organism  in  the  course  of  which  it 
comes  to  offer  a  more  favorable  soil  for  the  proHferation  of  mahgnant 
new  growths. 

Flexner  and  JobHng^  described  a  series  of  experiments  in  which 
rats  were  treated  intraperitoneally  with  an  emulsion  of  adeno- carcinoma 
that  had  been  heated  for  half  an  hour  at  56°  C.  Grafts  of  the  same 
tumor  introduced  subcutaneously  into  these  rats  twenty-four  hours 
afterward  grew  at  the  same  rate  as  the  grafts  implanted  in  controls. 
But  when  tumor  was  inoculated  from  ten  to  thirty  days  following  the 
injection  of  heated  emulsion,  not  only  did  the  number  of  successful 
inoculations  tend  to  exceed  that  in  the  controls,  but  the  individual 
growths  developed  with  greater_rapidity,  reached  a  size  more  than 
double  that  of  the  control  tumors,  and  showed  a  far  smaller  percent- 
age of  retrogressions.  The  promoting  influence  was  less  effective  at 
thirty  days  than  at  ten,  but  indications  existed  which  seemed  to  show 
that  if  the  preliminary  treatment  were  repeated  once  or  twice  at  ten- 
day  intervals,  the  conditions  favoring  the  growth  and  persistence  of 
the  tumors  could  be  maintained,  and,  possibly,  still  further  increased. 

In  a  second  article  the  authors  -  recorded  an  analysis  of  the  phenom- 
enon previously  described.  One-half  of  a  group  of  rats  with  station- 
ary or  receding  growths  was  inoculated  with  heated  emulsion  and  ten 
days  later  with  tumor,  as  a  result  of  which  60  %  developed  growths. 
The  other  half  was  inoculated  without  an  antecedent  injection  of 
heated    emulsion,   and  in    only  36  %   was   the  outcome  successful. 

^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1906-1907,  iv,  156. 
"^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1907-1908,  v,  16. 


HYPERSUSCEPTIBILITY  1 79 

Normal  control  rats  yielded  loo  %.  In  a  similar  experiment  carried 
out  on  a  second  group  of  rats  in  which  the  growing  tumor  was 
later  absorbed,  only  9  %  of  those  that  had  not  received  heated 
tumor  emulsion  were  successfully  inoculated,  while  tumors  de- 
veloped in  30  %  of  those  that  had  been  subjected  to  preliminary 
treatment. 

Again,  a  series  of  rats  injected  with  heated  emulsion  and  successfully 
inoculated,  the  tumors  having  finally  undergone  absorption,  was 
divided  into  two  parts.  One  of  these  groups  received  a  second  injec- 
tion of  heated  emulsion,  the  other  was  kept  for  controls.  At  the 
expiration  of  ten  days  both  groups  were  inoculated  with  tumor  grafts, 
in  consequence  of  which  30  %  of  each  developed  growths,  while 
100  %  occurred  in  the  normal  controls.  It  appeared,  therefore, 
that  no  promoting  effect  arose  from  a  second  injection  of  immune  rats 
with  heated  tumor  emulsion.  What  seemed  equally  surprising  was 
the  high  percentage  of  successful  secondary  inoculations  in  this  group, 
as  contrasted  with  the  low  percentage  among  the  rats  in  the  pre- 
ceding group  which  had  not  received  the  emulsion  — ■  that  is,  30  % 
against  9  %.  If,  however,  this  group  were  compared  with  the 
one  in  which,  after  spontaneous  recovery,  heated  emulsion  was  in- 
jected for  the  first  time  and  followed  by  new  grafts,  the  percentage 
of  successful  re-inoculations  was  found  to  be  identical  in  both, 
namely,  30  %. 

The  authors  thought  it  premature  to  attempt  a  discussion  of 
these  results,  which  seemed  to  imply  that  by  the  injection  of  heated 
tumor  emulsion  a  state  of  susceptibility  to  implantation  could  be 
preserved,  while  at  the  same  time  the  tumor  originally  implanted 
had  undergone  absorption. 

No  promotion  of  growth  foUowed  previous  treatment  with  heated 
and  unheated  emulsions  of  various  organs,  or  with  the  sera  of  normal 
rats,  of  naturally  resistant  rats,  of  rats  that  had  acquired  resistance 
through  the  absorption  of  their  tumors,  or  of  rats  with  growing 
tumors. 

Gaylord  ^  repeated  these  experiments  with  a  sarcoma  of  the  rat, 
but  was  unable  to  demonstrate  hypersensitiveness,  or  any  definite 
condition,  following  the  injection  of  heated  tumor  material. 

1  Jour.  American  Med.  Assoc,  1908,  li,  252. 


l8o  ^  HYPERSUSCEPTIBILITY 

BasMord.  ]\Iurray.  and  Haaland  ^  had  found  that  if  a  dose  of 
spontaneous  tumor  not  exceeding  o.i  cubic  centimeter  were  used  in 
an  attempt  to  produce  resistance  the  effect  was  usually  not  very 
pronounced,  and  that  when  inoculation  was  performed  after  a 
long  interval  a  condition  of  h}-persu5ceptibiHty  might  be  sho^\'n  to 
exist. 

They  had  seen  evidence  supporting  the  occurrence  of  the  same  condi- 
tion after  the  inoculation  of  mouse  mamma-  and  skinless  mouse  em- 
bryo. The  treatment  of  mice  ^^dth  rat  mamma,  six  weeks  before 
tumor  implantation,  had  also  evolved  a  state  of  hj'persensibiHty, 
although  where  such  treatment  preceded  the  inoculation  of  the  tumor 
by  only  sixteen   days,  none  was    apparent. 

It  seemed  to  the  authors  that  both  the  time  interval  and  the  dose  of 
normal  tissue  emplo3"ed  were  of  importance  in  determining  whether 
protection  or  h^-persusceptibility  would  super^'ene.  H^-persensibility 
seemed  to  be  a  less  specific  phenomenon  than  resistance,  and  one 
that  could  be  obtained  by  prehminarv-  treatment  with  various  sub- 
stances, particularly,  however,  wdth  the  tissues  of  strange  species. 

]\Ioreschi  ■'  observed,  after  two  injections  of  lactating  mouse 
mamma,  a  distinct  stimulation  of  growth  when  tumor  inoculation 
was  performed  from  ten  to  twelve  days  after  the  last  treatment. 
PreHminary  injection  of  mice  with  functionating  rat  mamma  favored 
proliferation  in  two  different  strains  of  carcinoma,  when  the  interval 
between  treatment  and  the  introduction  of  the  graft  was  from  nine 
to  fifteen  days.  But  if  the  tumor  were  inoculated  after  from  thirty 
to  thirty- seven  days  the  growth  stimulus  was  repressed,  to  be  sup- 
planted by  a  distinct  resistance.  Lactating  guinea-pig  mamma  did 
not  produce  h\'persusceptibLlity. 

Gay  "^  found  that  the  blood  of  normally  insusceptible  rats  or  of  rats 
unsuccessfully  inoculated  "^dth  the  Flexner-Jobhng  adeno-carcinoma, 
injected  into  normally  insusceptible  rats  before  tumor  inoculation, 
or  concomitantly  wdth  it,  led  to  a  larger  percentage  of  growths. 

1  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  368,  376,  381. 

2  See  plate  facing  page  144. 

^  Zeitschrifl  f.  Immiinitdtsforsch.,  etc.,  Orig.,  1909,  ii,  675. 
^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1908-1909,  \'i,  75. 

Jour.  Med.  Research,  1909,  N.S.,  x\^,  186. 

Boston  Med.  atid  Surg.  Jour.,  1909,  clxi,  211. 


HYPERSUSCEPTLBILITY  l8l 

According  to  Haaland.^  an  obvious  h}-per5en5ibility  followed  the 
inoculation  of  cancerous  or  normal  cells  that  had  been  mechanically 
disintegrated  by  freezing  and  grinding.  That  this  condition  was  not 
a  phase  antecedent  to  the  estabhshment  of  resistance  was  demonstrated 
by  var\-ing  the  time  inter^'al  between  prehminar}'  treatment  and 
tumor  implantation,  from  which  it  became  apparent  that  there  was  as 
Httle  immunity  after  thirty  days  as  after  ten  or  twenty.  A  dose  of 
O.I  cubic  centimeter  of  disintegrated  tissue  appeared  to  produce 
the  optimum  of  hypersusceptibihty.  Animals  could  also  be  h^^ersen- 
sitized  -^^-ith  0.5  cubic  centimeter  of  the  expressed  fluid  of  cancer  or 
normal  tissue,  or  through  treatment  with  cells  devitahzed  by  autolysis, 
heat,  or  exposure  to  radium. 

Leitch-  observed  h}-persen5ibility  in  mice  that  had  been  treated 
with  the  supernatant  fluid  from  an  em^ulsion  of  ground  mouse  can- 
cer cells  in  physiological  sahne  solution.  The  fluid  was  injected 
into  the  peritoneum  on  three  occasions  at  ten-day  intervals,  one- 
half  a  cubic  centimeter  at  the  first,  and  one  centimeter  at  the  last 
two  treatments,  and  tumor  inoculation  was  undertaken  twenty-four 
days  after  the  last  injection.  The  amount  introduced  represented, 
in  the  opinion  of  the  author,  an  exceechngly  minute  dose  of 
epithelium. 

Uhlenhuth,  Haendel,  and  Stefi'enhagen  ^  were  of  the  impression 
that  in  rats  pre^dously  treated  with  the  serum  of  resistant  rats,  tumor 
development  and  growth  were  favorably  influenced.  H}'persensi- 
bihty  was  noted,  also,  when  tumor  emulsion  had  been  mixed  before 
inoculation  ^^-ith  the  serum  of  resistant  rats. 

Another  type  of  sensibility  to  tumor  cells  was  described  by  Yama- 
nouchi,'*  wherein  mice  bearing  tumors  were  said  to  react  immediately, 
and  with  very  characteristic  s}miptoms,  to  the  intraperitoneal  inocula- 
tion of  an  emulsion  of  the  same  tumor.  The  pathognomonic  S}TQp- 
toms,  a  Staring  coat  and  a  condition  of  immobihty  followed  after 
twenty-four  hours  by  death,  occurred  neither  in  normal  mice,  nor  in 

'  Proc.  Roy.  Soc,  Series  B,  1909-1910,  Lxxxii,  293. 

Lancet,  1910,  i,  787. 
^Lancel,  1910,  i,  991. 
^  Centralbl.f.  BakL,  etc.,  erste  Abt.,  Ref.,  1910,  xlvii,  Beiheft,  164. 

Arb.  a.d.  Kaiserl.  Gesiindheitsamte,  191 1,  xxxva,  490. 
*  Compt.  roid.  Soc.  Biol.,  1909,  lx\a,  754. 


152  HYPERSUSCEPTIBILITY 

those  whicli  had  been  unsuccessfully  inoculated.  That  mice  in  the 
latter  category  were  not  affected  seemed  to  demonstrate  that  the  con- 
dition was  not  an  anaphylaxis  (in  the  usual  sense  of  the  word)  toward 
the  tissue  of  the  tumor. 

Apolant  ^  was  unable  to  reproduce  this  phenomenon,  and  offered  the 
tentative  explanation  that  Yamanouchi's  growth  had  been  infected, 
and  that  the  hypersensibiHty  had  been  directed  toward  bacteria 
rather  than  toward  tumor  cells. 

Similarly,  the  experiments  of  Rous^  did  not  support  the  findings 
reported  by  Yamanouchi. 

ANAPHYLAXIS 

Pfeiffer  and  Finsterer  ^  found  that  guinea-pigs  which  had  received 
forty-eight  hours  previously  an  intraperitoneal  inoculation  of  the 
serum  of  a  carcinomatous  individual,  showed  anaphylactic  symptoms 
(among  them  a  drop  of  several  degrees  in  the  body  temperature)  upon 
injection  of  the  expressed  juice  of  the  patient's  tumor.  A  similar  re- 
action could  be  produced,  also,  in  an  animal  sensitized  with  the  serum 
of  a  person  other  than  the  one  furnishing  the  tumor,  so  that  a  patient 
with  carcinoma  seemed  to  produce  anaphylactic  antibodies,  not  only 
against  his  own  tumor,  but  against  carcinomata  in  general, 

Ranzi,^  who  said  that  he  had  not  found  the  reaction  specific,  was 
criticized  by  Pfeiffer,^  chiefly  upon  technical  grounds. 

^  Zeitschrift  f.  Immu)iitdtsforsch.,  etc.,  Orig.,  1909,  iii,  108. 
^  Zeitschrift  f .  Immunitdtsforsch.,  etc.,  Orig.,  1910,  iv,  238. 

'  Wien.  klin.  Woch.,  1909,  xxii,  989.  See  also  Pfeiffer,  Wien.  klin.  Woch.,  1909,  xxii, 
1227. 

^Wien.  klin.  Woch.,  1909,  xxii,  1372. 
^V/ien.  klin.  Woch.,  1909,  xxii,  1375. 


r^j 


> 

*-»- 

\      \  ''■. 

ym  m  ^r^^^9''/^3v^^ 


'<  C?i.^- 


.'    '/ 


Adeno-carcinoma  from  small  intestine  of  the  mouse.     Margin  of  growth,  showing  mode  of  extensior 
laterally  and  through  muscular  wall.     X  -r  • 


CHAPTER  VII 

THE   SPONTANEOUS   TUMOR 
FREQUENCY    OF    TUMORS    AMONG    THE    LOWER    ANIMALS 

To  review  fully  the  occurrence  of  spontaneous  tumors  among  the 
lower  animals  is  not  within  the  scope  of  this  volume.  It  is  sufficient  for 
the  present  purpose  merely  to  state  that  both  benign  and  malignant 
tumors  are  being    discovered  constantly  in    mammals,   birds,   am- 


FiG.  8.  —  Grouse  :  Primary  adeno-carcinoma  of  small  intestine.  Infiltrative  growth 
in  all  the  coats,  great  thickening  of  circular  muscular  layer,  the  surface  of  which  at  one 
part  forms  the  base  of  the  ulcer.      X  Y- 

183 


184  THE    SPONTANEOUS   TUMOR 

phibians,  and  fish,  and  that  the  close  degree  of  relationship  with  man 
into  which  many  of  the  subjects  are  thrown  has  not  been  proved  in 
the  slightest  degree  responsible  for  the  development  of  the  disorder. 
If  malignant  disease  be  more  common  among  the  domestic  animals 
it  is  only  because,  as  Bashford  and  Murray^  have  pointed  out,  enjoy- 
ing a  longer  span  of  life  by  reason  of  man's  care  more  of  them  reach 
the  cancer-bearing  age,  and  because  they  are,  moreover,  under  more 
constant  observation  than  are  animals  living  in  a  state  of  nature. 

The  zoological  distribution  of  cancer  has  been  discussed  by  these  two 
authors  together,  and  by  Murray  alone ,-  and  they  have  recorded,  among 
tumors  observed  by  themselves  or  others,  malignant  growths  in  the 
cow,  dog,  horse,  sheep,  pig,  cat,  hen,  Indian  parakeet,  macaw,  grouse, 
canary,  giant  salamander,  frog,  triton,  codfish,  gurnard,  and  trout. 
According  to  Murray,  no  case  of  malignant  tumor  has  yet  been  found 
among  the  reptiles,  although  Pettit  described  a  fibroma  of  the  stomach 
in  a  python,  and  Koch  a  papilloma  of  the  occipital  region  in  a  lizard. 

The  occurrence  of  malignant  or  benign  tumors  and  the  literature 
germane  to  this  subject  have  been  discussed  by  Sticker,^  Ehrenreich 
and  Michaelis,^  Plehn,^  Casper,^  Tyzzer  and  Ordway/  Fiebiger,^  and 
McCoy.9 

Instances  of  growths  apparently  malignant  have  been  reported, 
furthermore,  in  the  vegetable  kingdom,  none  of  them,  however,  so 
convincing  as  Jensen's^*'  transplantable  tumor  of  the  beet. 

STRUCTURE    OE   ORIGIN    IN    THE    MOUSE 

When  pathologists  began  to  interest  themselves  in  tumors  of  the 
lower  animals,  preeminently  in  those  of  rats  and  mice,  and  to  attempt 
transplantation,  the  first  question  that  had  to  be  answered  was  whether 
these  growths  were  actually  malignant.     The  gravest  doubts  of  their 

^  Sci.  Reports,  Cancer  Research  Fund,  London,  1904,  No.  1,5. 
2  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  41. 
^  Arch.  f.  klin.  Chir.,  (v.  Langenbeck),  1902,  Ixv,  616,  1023. 

^  Zeitschrift  f.  Krebsforsch.,  1906,  iv,  586.         ^  Zeitschrift  f.  Krebsforsch,  1906,  iv,  525. 
^  Ergebn.  d.  allg.  Path.,  etc.,  (Lubarsch  and  Ostertag),  1907,  xi,  Abt.  2,  1068. 
''Jour.  Med.  Research,  1909,  N.S.,  xvi,  459. 
*  Zeitschrift  f.  Krebsforsch.,  1908-1909,  vii,  165,  371,  382. 
'  Jour.  Med.  Research,  1909,  N.S.,  xvi,  285. 
1°  Travaux  de  la  deuxieme  Conference  internat.  pour  l' Etude  du  Cancer,  Paris,  191 1,  243. 


■^% 


Aa 


'J^y 


Malignant  adeno-carcinoma  of  skin  glands  from  frog.     The  growth  has  penetrated  beneath  the  dense 
lamellar  layer  of  the  dermis,  a,  and  infiltrates  the  subjacent  muscles  of  the  thigh,  b.     X  -*r. 


(5 


'J><^ 


fr 


®/ 


1^® 


o '%  ao'of 
'®a«     s>  «>  til 


Same  growth,  showing  connection  with  normal  skin,  the  tumor  apparently  spreading  laterally  along  its 


deep  surface 


Photograph  by  Dr.  Zarnib. 

Carcinoma  of  skin  glands  from  triton.     Macroscopic  appearance  of  growth  at  angle  of  mouth  and 

scattered  nodules  on  tail.     X  $. 


J.  R.  Ford,  del. 
High  power  view  of  above  growth.     Alveolar  part  of  tumor  and  commencement  of  a  columnar  cell 
portion  (right  upper).     Note  how  sharply  the  alveolar  plugs  are  marked  off  from  the  surrounding 
normal  skin.     X  V. 


Micropliulugraph  by  li.  Muir. 

Osteo-sarcoma  of  operculum  from  cod.     Portions  of  two  osseous  nodules  are  shown,  with  surrounding 

vascular  spindle  cell  tissue.     X  t°- 


THE   SPONTANEOUS   TUMOR  185 

true  neoplastic  nature  existed  on  many  sides,  and  the  patient  collec- 
tion of  data  regarding  their  life  history  was  necessary  before  the  prob- 
blem  could  be  settled.  In  addition,  one  of  the  most  important  tasks 
was  to  determine  the  structure  giving  origin  to  the  tumors,  a  ques- 
tion to  which  the  answer  at  the  beginning  of  the  investigation  was 
by  no  means  certain. 

Eberth  and  Spude  ^  had  described  tumors  in  three  mice  and  had  at- 
tempted to  transplant  these  growths,  but,  puzzled  by  the  lack  of  apparent 
connection  between  the  neoplasms  and  any  epithelial  structure,  con- 
cluded that  they  were  endotheliomata,  in  spite  of  their  morphology. 
As  Apolant  ^  said  later,  however,  if  these  authors  had  only  examined 
a  section  of  normal  mouse  mamma,  they  never  would  have  mistaken 
ducts  and  alveoli  for  altered  lymph  vessels. 

The  ostensible  want  of  relationship  between  epithelial  structures 
and  tumors  seemingly  of  epithelial  origin  continued,  nevertheless,  to 
confuse  many  of  Eberth  and  Spude's  successors.  Jensen,^  although  not 
certain  of  the  source  of  his  tumor,  was  inclined  to  derive  it  from  the 
glandular  structures  of  the  skin  or  from  the  epidermis,  while  Pick  and 
Poll  ^  described  an  epithelial  tumor  of  the  scapular  region  in  a  white 
mouse  and  suggested  that  it  had  originated  in  the  sweat  glands.  Ac- 
cording to  both  Apolant  ^  and  Murray,^  however,  the  sweat  glands  of 
the  mouse  are  restricted  to  thte  soles  of  the  feet. 

V.  Hansemann  "^  expressed  the  opinion  that  the  tumors  found  in 
mice  did  not  proceed  from  the  skin,  nor  did  he  consider  that  they  were 
of  glandular  origin,  and  held  that  the  hibernating  gland  should  be  con- 
sidered in  any  attempt  to  account  for  their  genesis.  This  gland,  a 
structure  of  very  extensive  distribution  extending  from  between  the 
shoulders  forward  to  the  thymus,  running  thence  toward  the  aorta  and 
widening  out  on  either  side  to  reach  finally  the  region  of  the  kidney, 
was  not  found,  however,  in  the  neighborhood  of  the  inguinal  folds,  where 

^  Arch.  f.  path.  Anat.,  etc.,  (Virchow),  1898,  cliii,  60. 
^  Arh.  a.  d.  Konigl.  Inst.'f.  Exp.  Therap.,  1906,  Heft  i,  32. 
^  Centralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1901,  xxxiv,  i,s- 
^  Berl.  klin.  Woch.,  1903,  xl,  519. 

^  Arb.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  40. 
®  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  85. 
'  Verhandl.  d.  Komitees  f.  Krehsforsch.,  1903-1904,  iii.  38.     See  also  Deut.  med.  Woch., 
19,04,  XXX,  1264. 


1 86  THE    SPONTANEOUS   TUMOR 

tumors,  nevertheless,  not  infrequently  originate.  He  was  inclined,  on 
the  whole,  to  believe  that  the  growths  were  derived  from  endothelium, 
although  he  confessed  his  inability  to  advance  proof  of  this  contention. 

MichaeHs,^  because  of  the  alveolar  structure  of  Jensen's  tumor, 
raised  the  question  whether  it  might  not  represent  an  adenomatous 
growth  springing  from  a  gland  without  lumina,  and  suggested  the 
two  glands  of  this  type  found  in  the  mouse  at  the  sides  of  the  trachea. 

The  studies  of  Bashford  and  Murray,^  and  of  Apolant,^  were  the 
first  to  fix  definitely  the  tissue  from  which  originated  the  great  majority 
of  the  epithelial  tumors  of  the  mouse.  Apolant,  having  noticed  that 
nearly  all  tumors  occurred  among  females  on  the  ventral  aspect  of  the 
body,  was  led  to  inquire  what  subcutaneous  structure  was  limited  to 
this  surface  of  the  animal,  extended  from  the  jaw  to  the  region  of  the 
genitals,  and  was  best  developed  in  females.  The  mammary  glands  met 
the  requirements  so  adequately  that  Apolant  could  not  escape  accept- 
ing them  as  the  organs  giving  origin  to  the  tumors.  Of  these  glands 
the  mouse  possessed  five  on  each  side,  the  forward  pair  of  which 
abutted  directly  upon  the  submaxillary  glands,  while  that  nearest  to  the 
caudal  end  of  the  animal  was  in  close  proximity  to  the  vulva.  Micro- 
scopic examination,  furthermore,  demonstrated  absolutely  a  mammary 
genesis  for  most  of  the  tumors,  and  made  it  extremely  probable  for  the 
remainder. 

Similar  observations  by  Bashford  and  Murray  estabhshed,  in  ad- 
dition, a  mammary  origin  even  for  tumors  situated  upon  the  back. 
They  found  that  the  five  pair  of  mammary  glands  occupied  the  sides 
and  front  of  the  body  from  the  neck  to  the  anus,  and,  extending  at 
the  shoulders  around  the  sides  of  the  thorax  both  behind  and  in  front 
of  the  fore-Kmbs,  met  dorsally  in  the  middle  fine.  At  the  inguinal 
region  there  was  a  similar  extension  along  the  crest  of  the  ihum  and 
over  the  inner  aspect  of  the  thigh.  Histological  proof  of  the  mammary 
origin  of  these  tumors  was  not  wanting,  for  it  was  found  that  they 
formed  a  graduated  series,  extending  from  growths  built  up  of  small 
acini  indistinguishable    from  those  of  the  normal    resting   mamma, 

1  Verhandl.  d.  Kofnitees  f.  Krehsforsch.,  1903-1904,  iii,  37.  See  also  Deut.  med.  Woch., 
1904,  XXX,  1264. 

2  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  15.  Lancet, 
1907,  i,  798.     Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  83. 

^  Arb.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  17. 


THE    SPONTANEOUS    TUMOR  187 

through  others  in  which  the  acini  were  dilated  into  cystic  spaces 
reproducing  in  exaggerated  form  the  puerperal  condition,  to  alveolar 
growths  built  on  the  plan  of  the  rapidly  growing  mammary  founda- 
tion of  the  new-born  mouse.  Tumors  of  other  types  were  also  en- 
countered in  the  mamma  —  angiomata,  sarcomata,  and  squamous  cell 


Fig.  9. —  Mouse  :     Sites  of  142  spontaneous  mammary  carcinomata,  shown  by  black 

dots ;  nipples  by  stars. 

carcinomata,  and  in  a  proportion  analogous  to  that  met  with  in  mam- 
mary neoplasms  of  the  human  subject. 

Deton,^  having  reconstructed  wax  models  from  serial  sections  of 
two  spontaneous  carcinomata  from  the  mammary  region  in  the  mouse, 
concluded  that  the  tumors  had  not  originated  in  the  mamma. 
Apolant,^  however,  could  not  accept  this  view,  because,  in  his  opinion, 
the  method  was  not  sufficiently  accurate  to  demonstrate  the  relations 
existing  between  tumor  and  mamma. 

It  has  been  said  frequently  that  new  growths  in  the  mouse  oc- 
curred solely  in  the  mamma,  and  that  their  analogy  with  malignant 
new  growths  in  the  human  subject  was  materially  lessened  by  this 

1  Zeitschrijt  f.  Krebsjorsch.,  1909-1910,  viii,  459. 
^  Arch.  f.  mikroskop.  Anal.,  1911,  bcxviii,  156. 


l88  THE    SPONTAKEOUS   TUMOR 

observation.  That  the  belief  was  erroneous,  however,  will  appear  from 
the  most  cursory  review  of  the  Kterature,  and  it  is  only  necessary  to 
direct  attention  to  a  few  of  the  recorded  tumors  to  show  that  the  types 
of  neoplasia  found  in  the  mouse  have  been  as  divers  as  in  man.  Thus 
Borrel  ^  found  a  squamous  cell  carcinoma  of  the  floor  of  the  mouth 
and  Haaland  ^  four  similar  cases,  while  Bashford,  Murray  and  Cramer,^ 
and  Murray  ^  alone,  have  reported  a  series  of  growths,  among  which 
were  an  adeno- carcinoma  of  the  small  intestine,  a  squamous  cell  car- 
cinoma of  the  stomach,  a  spindle  cell  sarcoma  of  the  kidney  region, 
and  an  adenoma  of  the  liver,  probably  malignant.  Ehrlich  and  Apo- 
lant^  have  described  a  spontaneous  carcinoma  sarcomatodes,  Ehrlich  ^  a 
chondroma,  and  Haaland  "^  a  melanoma  of  the  ear,  an  adeno-carcinoma 
of  the  kidney,  a  hypernephroma  ( ?) ,  an  adeno-carcinoma  of  the  ovary 
(probably  primary),  a  fibro-myoma  of  the  uterus,  two  adeno-carcino- 
mata  of  the  perputial  gland,  several  sebaceous  adeno-carcinomata, 
three  squamous  cell  carcinomata  of  the  mouth,  a  spontaneous  car- 
cinoma sarcomatodes,  and  several  sarcomata.  Multiple  tumors  oc- 
curred in  17  %  of  Haaland' s  cases,  as  compared  with  15  %  in 
Murray's  series,  and  12  %  in  Apolant's. 

In  the  rat,  sarcomata  have  been  described  by  Loeb,^  Herzog,^  and 
Jensen,^°  a  fibro-epithehoma  of  the  tongue  by  Stahr,^^  an  adeno-carci- 
noma of  the  seminal  vesicle  by  Flexner  and  Jobling,^^  and.  a  car- 
cinoma of  the  mamma  by  Lewin  and  Michaelis.-^^ 

1  Cited  by  Haaland,  Ann.  de  VInst.  Past.,  1905,  xix,  188. 

2  Ann.  de  VInst.  Past.,  1905,  xix,  188. 

^  Set.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  47. 

*  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  69. 

^  Berl.  klin.  Woch.,  1907,  xliv,  1399. 

^  Arb.  a.  d.  Konigl.  Inst.f.  Exp.  Therap.,  1906,  Heft  i,  65. 

''  Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1911,  i. 

^  Jour.  Med.  Research,  1901,  N.S.,  i,  28.        ^  Jour.  Med.  Research,  1902,  N.S.,  iii,  74. 

^°  Zeitschrift  f.  Krebsforsch.,  1908-1909,  vii,  45. 

^^  Centralbl.  f.  allg.  Path.,  etc.,  1903,  xiv,  i. 

^^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1906-1907,  iv,  12. 
Monographs  on  Medical  and  Allied  Subjects,  Rockefeller  Institute,  New  York,  1910, 
No.  I,  p.  I. 

Flexner  and  Jobling  at  first  reported  their  tumor  as  a  sarcoma.  During  continued 
propagation,  however,  it  altered  in  character;  in  later  articles  {Proc.  Soc.  Exp.  Biol,  and 
Med.,  1908,  V,  52,  91)  the  authors  described  the  gradual  ascendancy  of  epithelial  elements 
(discovered  upon  reexamination  in  the  spontaneous  tumor)  and  disappearance  of  struc- 
tures previously  thought  to  be  sarcomatous.     The  tumor  is  now  an  adeno-carcinoma. 

1^  Deut.  nied.  Woch.,  1907,  xxxiii,  657.  See  also  Lewin,  Berl.  klin.  Woch.,  1907,  xHv.  1602. 


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THE    SPONTANEOUS    TUMOR  189 

V.  Hansemann,^  while  not  denying  the  occurrence  of  carcinoma 
in  the  mouse  and,  indeed,  admitting  that  Borrel's  tumors  were  true 
carcinomata,  was  incHned  to  place  Jensen's  among  the  endothehomata. 
Certainly,  he  ^  contended,  Bashford  was  unwarranted  in  calling  it 
a  carcinoma  solely  because  it  produced  metastases,  for  secondary 
deposits  were  found  in  connection  with  many  endothehomata.  In 
order,  however,  to  be  convinced  of  the  endotheHal  nature  of  these 
neoplasms  it  was  necessary  to  examine  the  spontaneous  tumors,  for 
in  transplanted  growths  the  evidence  was  not  so  striking. 

Lazarus-Barlow^  concurred  in  the  opinion  that  the  tumors  found  in 
mice  were  more  properly  classed  among  the  endothehomata. 

THE   QUESTION    OF   MALIGNANCY 

Occurrence  of  Metastases 

Jensen  and  all  others  who  believed  in  the  malignancy  of  his  tumor 
were  very  severely  arraigned  by  Wilhams,^  who  asserted  that  they  had 
relied  too  much  on  histological  appearance  and  not  enough  on 
chnical  observation,  and  ascribed  to  their  narrow  outlook  the  "ex- 
traordinary concatenation  of  blunders  with  which  the  liistory  of  the 
experimental  study  of  cancer  is  cumbered." 

Such  a  statement,  however,  scarcely  does  justice  to  the  care  which 
the  investigators  of  experimental  cancer  have  bestowed  upon  the  clini- 
cal course  of  the  disease  in  the  mouse  and  rat,  for  one  of  the  most 
eagerly  prosecuted  inquiries  has  been  that  relating  to  the  presence  or 
absence  of  metastasis  formation  and  infiltrative  growth. 

As  early  as  1896,  Livingood  °  discovered  in  the  shoulder  region  of 
a  white  mouse,  an  adeno-carcinoma  which  not  only  recurred  several 
months  after  removal,  but  produced  a  metastatic  deposit  in  the  lung. 
In  another  mouse,  with  a  carcinoma  on  the  fore-leg,  there  were  several 
secondary  tumors  in  the  lung  and,  as  in  the  first  case,  they  were  of 
the  same  structure  as  the  primary  growth. 

^  Berl.  klin.  Woch.,  1905,  xlii,  315.  ^  Zeitschrift  f .  Krebsforsch.,  1905,  iii,  570. 

^  Proc.  Roy.  Soc.  Med.,  1908,  i,  Path.  Section,  171. 
■*  Trans.  Path.  Soc.  London,  1907,  Iviii,  38. 

The  Natural  History  of  Cancer,  New  York,  1908,  187. 
^  Johns  Hopkins  Hosp.  Btdl.,  1896,  vii,  177. 


I  go  THE    SPONTANEOUS   TUMOR 

Loeb  ^  found  metastases  in  rats  with  transplanted  tumors,  and  sit- 
uated in  regions  which  they  could  have  reached  only  through  transpor- 
tation by  the  blood  or  lymph  streams.  He  pointed  out  that  rats  bear- 
ing propagable  neoplasms  did  not  live  for  more  than  two  or  three 
months,  and  that  it  was  perhaps  necessary,  as  in  man,  that  the  growth 
be  present  during  a  longer  period  in  order  that  secondary  deposits 
might  occur. 

Borrel  ^  discovered  metastases  in  the  lungs  and  the  lymph  nodes 
of  mice  bearing  tumors,  and  Haaland  ^  concluded,  after  an  examina- 
tion of  serial  sections  of  the  organs  of  mice  spontaneously  affected 
with  cancer  and  of  those  inoculated  with  the  Jensen  carcinoma,  that 
metastasis  by  way  of  the  blood  stream  was  of  common  occurrence, 
at  least  in  association  with  growths  which  were  at  all  advanced  in  age. 
Among  six  cachectic  mice  bearing  Jensen's  tumor  he  found  pulmonary 
nodules  in  five,  although  he  was  able  to  confirm  Jensen's  statement  that 
metastases  could  not  be  detected  in  the  Ijnnph  nodes,  while  among  spon- 
taneously affected  mice  lymphatic  deposits  were  difficult  to  demon- 
strate, and  might  be  considered  rare.  Even  after  a  much  more  extensive 
experience  with  spontaneous  tumors,  Haaland  ^  had  not  found  the 
lymph  nodes  involved  nearly  so  often  as  the  lungs,  in  which  metastatic 
nodules  clearly  visible  to  the  naked  eye  were  discovered  in  38  %  among 
two  hundred  and  seventy-three  cases.  In  other  locations,  however, 
secondary  deposits  were  much  more  rare,  occurring  but  four  times  in 
the  Hver,  once  in  the  kidney,  once  possibly  in  the  ovary,  thrice  on  the 
peritoneum,  once  in  the  retroperitoneal  tissue  at  the  site  of  the 
adrenal,  once  under  the  diaphragm,  once  in  the  posterior  medias- 
tinum, and  once  in  the  spleen.  In  one  case  the  cells  of  a  lung 
metastasis  had  grown  through  the  vessels  into  the  heart,  where  they 
floated  free  in  the  blood  stream. 

Bashford  and  Murray,^  in  the  earliest  days  of  their  experience  with 
the  Jensen  tumor,  failed  to  discover  secondary  nodules,  but  in  the 
following  year,  in  collaboration  with  Cramer,^  described  them  in  the 
lungs  of  mice  inoculated  with  this  growth, 

1  Jour.  Med.  Research,  1902,  N.S.,  iii,  48.      ^  Ann.  de  I'Inst.  Past.,  1905,  xix,  172,  184. 

^  Ann.  de  I'Inst.  Past.,  1903,  xvii,  114.  Deut.  med.  Woch.,  1905,  xxxi,  1239. 

*  Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  191 1,  54. 

^  Sci.  Reports,  Cancer  Research  Fund,  London,  1904,  No.  i,  13  (footnote). 

^  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  38. 


;.^'/?'      -•'•.-••!••■  J/.  ••'•?r   /•.   •     .v.  ...       .  .•■/ 


•.V-.-  .".■   •   . '•••'•^jXVi^r'c^r^v;^^ 


#^&^^^^ 


■^;^|^ 


■■-  •■■■  1 
■••••.p. 


X  fl.  Ford,  del. 
Metastasis  in  cervical  lymph  node  of  the  mouse,  from  a  spontaneous  mammary  carcinoma.     X  ^. 


Metastasis  in  aortic  lymph  node  of  the  mouse,  from  another  spontaneous  mammary  carcinoma,  i.v.c, 
inferior  vena  cava ;  u,  ureter.  The  growth  has  expanded  the  capsule  of  the  gland  and  the  lymphoid 
tissue  is  reduced  to  a  crescent.     X  ^r. 


THE    SPONTANEOUS   TUMOR  I9I 

Murray  ^  found  metastases  in  the  lung  in  rather  less  than  50  %  of 
sixty-eight  mice  with  spontaneous  tumors,  even  though  these  organs  had 
not  been  completely  investigated  in  all  the  cases,  and  Gierke  -  dis- 
covered secondary  nodules  in  the  same  location  in  eight  out  of  thirty- 
five  cases.  Lymphatic  metastases  were  detected  by  Murray  in  three 
cases  of  his  series,  and  by  Gierke  in  one. 

In  the  rat,  Flexner  and  Jobling^  reported  a  tumor  which  metas- 
tasized extensively  throughout  the  bodies  of  animals  into  which  it 
was  transplanted  and  which,  in  the  fifth  generation,  involved  even 
the  regional  lymph  nodes,  although  no  secondary  deposits  were  found 
in  the  animal  primarily  affected.  Michaelis  ^  discovered  in  the  same 
species  a  carcinoma  of  the  mamma  which,  although  it  had  not  given 
rise  to  metastases  in  the  rat  bearing  the  spontaneous  growth,  pro- 
duced them  after  inoculation,  nevertheless,  in  the  lungs,  Hver,  and 
glands  (Drusen)  of  other  rats. 

Infiltrative  Growth 

The  mahgnancy  of  the  tumors  of  mice  has  been  impugned  on  the 
further  ground  that  evidence  of  infiltrative  growth  had  never  been 
observed.  But  as  early  as  1904  Bashford  and  Murray  ^  had  investi- 
gated this  type  of  extension,  and  had  made  the  statement  in  a  foot- 
note that  the  malignancy  of  the  Jensen  tumor  was  demonstrated  by 
its  infiltrative  growth,  while  in  the  following  year  Bashford,  Murray, 
and  Cramer  ^  described  the  phenomenon  in  more  detail. 

Baeslack,'^  also,  had  discovered  infiltration  on  the  part  of  some 
tumors  of  the  Jensen  series.  Michaelis,^  on  the  contrary,  said  that 
infiltrative  growth  had  never  been  seen ;  and  although  a  year  later  he^ 

1  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  igo8,  98. 
^  Beitr.  zur  path.  Anat.,  etc.,  (Ziegler),  1908,  xliii,  331. 

Third  Sci.  Report,  Imperial  Cancer  Reicarch  Fund,  London,  1908,  118. 
^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1906-1907,  iv,  12. 

Jour.  American  Med.  Assoc,  1907,  xlviii,  420. 

Joiir.  American  Med.  Assoc.  1908,  1,  66. 
*  Zeitschrift  f.  Krebsforsch.,  1907,  v,  190.     See  also  Lewin  and  Michaelis,  Deid.  med. 
Woch.,  1907,  xxxiii,  657. 

^  Sci.  Reports,  Cancer  Research  Fund,  London,  1904,  No.  i,  13. 
^Sci.  Reports,  Imperial  Cancer  Research  Fund, 'London,  1905,  No.  2,  Part  ii,  39,  47. 
'  Dent.  med.  Woch.,  1905,  xxxi,  957.  ^  Deut.  med.  Woch.,  1904,  xxx,  1264. 

^  Med.  Klin.,  1905,  i,  203. 


192  THE    SPONTANEOUS   TUMOR 

still  felt  that  an  important  characteristic  of  maHgnancy  was  lacking 
while  this  method  of  extension  remained  midemonstrated,  a  brief 
note  ^  published  shortly  afterward  contained  the  affirmation  that  he 
had  observed  infiltration  in  certain  stages  of  his  tumors,  and  that  the 
last  distinction  betv/een  human  carcinoma  and  those  found  in  the 
mouse  had  thus  disappeared.  Metastases  he  had  been  able  to  demon- 
strate, once  in  the  lungs  and  once  in  the  lymph  nodes  in  two  mice 
with  spontaneous  tumors,  and  in  the  lungs  of  a  mouse  bearing  a 
transplantable  growth. 

The  explanation  of  Apolant^  that  infiltrative  growth,  although  it 
did  occur  in  the  mouse,  was  not  so  marked  as  in  human  beings  because 
the  tumors  developed  in  loose  connective  tissue,  where  they  had  an 
abundance  of  room  in  which  to  grow  without  involving  skin  and  mus- 
culature, was  entirely  in  harmony  with  the  observation  of  Bashford, 
Murray,  and  Cramer,^  that  the  Jensen  tumor  forsook  its  expansive 
growth  and  assumed  the  infiltrative  type,  when  dense  tissue  opposed 
its  progress. 

Bashford  and  Murray,^  in  a  detailed  account  of  sporadic  mammary 
carcinoma  in  the  mouse,  described  metastases  in  the  lymph  nodes  and 
lungs,  and  invasion  of  the  capsule  of  the  tumor  by  strands  and  colunms 
of  cancer  cells.  The  involvement  of  structures  adjacent  to  the  growth 
made  complete  surgical  ablation  possible  only  when  both  capsule  and 
surrounding  tissue  were  removed,  the  mere  shelHng  out  of  the  tumor 
from  its  capsule  having  been  found  inadequate.  Their  observations 
permitted  the  conclusion:  "...  that  we  are  dealing  with  new  growths 
of  the  mammary  region  of  the  mouse,  which  grow  progressively  (recur 
after  incomplete  removal) ,  infiltrate  the  surrounding  normal  tissues,  and 
produce  metastases  of  the  same  histological  type  in  the  lungs  and 
lymphatic  glands.  They  lead  to  the  death  of  the  animal."  Murray^ 
found,  indeed,  that  over  one-half  of  the  tumors  recurred  following  at- 
tempts at  total  excision,  after  an  interval  of  from  two  weeks  to  several 
months.  Furthermore,  he  had  been  able  to  demonstrate  by  histologi- 
cal examination  that  the  encapsulation  was  only  apparent. 

^  Med.  Klin.,  1905,  i,  496. 

^  Arh.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  60. 

^  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  40. 

*  Lancet,  1907,  i,  800. 

^  Jour.  Path,  and  Bad.,  1908,  xii,  437, 


THE    SPONTANEOUS    TUMOR  I93 

The  malignancy  of  mouse  tumors  was  adequately  defended  by 
Apolant  ^  in  a  recent  reply  to  v.  Hansemann's  objections  ^  against 
comparing  these  growths  to  those  of  man.  More  recently  still  v. 
Hansemann^  has  receded  from  his  original  position,  and  now  admits 
metastasis  to  be  an  occasional  event  attending  spontaneous  growths, 
although  still  denying  that  the  tumors  so  widely  regarded  as  mam- 
mary originate  in  the  mamma. 

The  two  main  objections  urged  against  the  malignancy  of  mouse 
and  ~at  tumors,  namely,  absence  of  metastases  and  of  infiltrative 
growth,  have  thus  been  overborne  by  a  mass  of  evidence  gradually 
collected  in  laboratories  throughout  the  entire  world. 

Altmann^s  Granules  as  a  Criterion  of  Malignancy 

The  question  of  the  malignancy  of  these  growths  was  attacked  from 
still  another  side  by  Beckton,"*  who  found  that  Altmann's  granules, 
although  they  were  demonstrable  in  most  of  the  varieties  of  normal  cells 
and  in  those  of  inflammatory  lesions  and  benign  tumors,  were  partly 
or  entirely  absent  from  the  cells  of  mahgnant  growths  in  the  human 
subject.  In  a  considerable  number  of  reputedly  mahgnant  dog  tu- 
mors which  this  author  had  the  opportunity  to  examine,  Altmann's 
granules  were  found  in  much  greater  numbers  than  in  mahgnant 
neoplasms  of  human  origin,  while,  as  concerned  normal  tissues,  the  gran- 
ules were  usually  missing  from  the  cells  of  stratified  squamous  epithe- 
Hum  and  unstriped  muscle.  In  the  embryos  of  the  mouse,  the  rat, 
and  the  chick,  granules  of  medium  or  small  size  were  discoverable 
in  moderate  numbers  in  the  earher  periods  of  development,  but  during 
the  later  stages  these  and  other  granules  might  be  either  present,  or 
absent  as  in  some  squamous  epitheha,  unstriped  muscle,  and  the 
epithehum  of  the  collecting  tubules  of  the  kidney. 

On  the  basis  of  these  observations  the  author  suggested  that  an  ex- 
amination for  the  presence  of  Altmann's  granules  might  yield  a  useful 
diagnostic  criterion  regarding  the  mahgnancy  of  a  given  tumor,  exclud- 

1  Berl.  klin.  Woch.,  191 2,  xlix,  495.  ^  Berl.  klin.  Woch.,  1912,  xlix,  224. 

^  Berl.  klin.  Woch.,  1913,  1,  81.  *  Jour.  Path,  and  Bad.,  1909,  xiii,  185. 

Arch.  Middlesex  Hosp.,  1909,  xv,  182.     Lancet,  1909,  ii,  391. 

British  Med.  Jour.,  1909,  ii,  859.  Jour.  Path,  and  Bad.,  1910,  xiv,  408. 

British  Med.  Jour.,  1910,  ii,  1422.  Arch.  Middlesex  Hosp.,  1910,  xix,  103,  iii,  115. 


194  THE    SPONTANEOUS    TUMOR 

ing,  of  course,  such  growths  as  had  arisen  from  tissues  that  did  not 
normally  contain  the  granules,  and  having  regard  to  the  anomalous 
position  occupied  by  ovarian  and  thyroid  tumors.  Turning  his  atten- 
tion to  tumors  of  the  mouse,  Beckton  examined  twenty-one  unselected 
examples  of  propagable  sarcomata  and  carcinomata,  two-thirds  of 
which  afforded  definite  e\'idenceof  mahgnancy  in  the  absence  of  granules 
from  their  cells,  while  in  the  remaining  third  the  granules  were  present. 
The  latter  group,  however,  Beckton  hesitated  to  stamp  as  non-malig- 
nant because  of  the  present  uncertain  state  of  available  knowledge 
on  the  subject.  While,  then,  Altmann's  granules  were  found  on  the 
whole  in  decidedly  greater  numbers  than  in  mahgnant  new  growths 
of  human  origin,  still,  in  about  two-thirds  of  the  cases  the  mouse 
tumors  were  as  devoid  of  granules  as  were  human  new  growths  of  un- 
doubted mahgnancy. 

Later  papers  by  Colwell  and  Beckton,^  Beckton  and  Colwell,^ 
Beckton  and  Russ,"  and  Miller/  dealt  with  various  technical  matters 
in  relation  to  the  granules  under  discussion. 

The  experience  of  Beckton  was  controverted  by  Bensley,'^  who 
beheved  that  the  cells  of  mahgnant  tumors  in  man  did  contain  Alt- 
mann's granules,  and  even  in  greater  number  than  they  could  be  de- 
tected in  the  tissues  from  which  the  tumors  arose. 

A  disagreement  as  to  the  granule  content  of  tumor  cells  is,  however, 
not  a  novelty,  for  while  Raum  ^  beheved  that  he  had  demonstrated 
the  presence  of  Altmann's  granules  in  the  cells  of  both  carcinomata 
and  sarcomata,  Burkhardt,^  on  the  other  hand,  was  convinced  that 
the  properties  of  the  cancer  cell  were  altered  in  such  a  way  as  to 
destroy  the  granules. 

In  any  case,  it  is  doubtful  whether  these  bodies  have  any  sig- 
nificant relation  to  the  biological  quaHties  of  a  tumor. 

^  Arch.  Middlesex  Hasp.,  1911,  xxiii,  41. 
2  Arch.  Middlesex  Hasp.,  191 1,  xxiii,  52. 
^  Arch.  Middlesex  Hasp.,  191 1,  xxiii,  99. 

*  Arch.  Middlesex  Hosp.,  191 1,  xxiii,  106. 

*  Trans.  Chicago  Path.  Soc,  igio,  viii,  78. 

^  Arch.  f.  mikroskop.  AnaL,  1892,  xxxix,  137. 
''Arch.J.  kiln.  Chlr.,  (v.  Langenbeck),  1902,  Ixv,  135. 


THE    SPONTANEOUS   TUMOR  I95 

AETIOLOGY 

Influence  of  Infectivity 

As  the  investigation  of  mouse  tumors  became  more  widespread, 
instances  of  apparent  contagion  through  the  medium  of  *'  cancer  cages" 
began  to  appear  in  the  Hterature.  Thus  Borrel  ^  recorded  a  breeding 
estabhshment  in  which  three  cases  of  cancer  had  occurred  in  a  single 
month.  Upon  making  a  visit  to  this  establishment  he  was  informed 
that  in  two  years  there  had  been  found,  in  the  same  cage,  more 
than  twenty  tumor  mice,  an  enormous  percentage  compared  with  the 
number  of  animals  kept  on  hand.  The  dealer  had  been  in  the  habit 
of  selling  the  young  mice,  and  the  growths  had  been  observed  solely 
in  the  older  ones  retained  for  breeding  purposes.  Borrel  offered  as 
further  evidence  of  infection  the  instance  of  a  cage  in  which  five  or 
six  cancers  had  arisen  during  one  year,  although  in  other  establish- 
ments, which  furnished  many  hundreds  of  mice  yearly,  no  case  had  ever 
been  discovered.  All  these  observations  pled  for  the  existence  of  a 
cancerous  virus,  a  conception  which  Borrel  ^  has  consistently  upheld 
in  subsequent  monographs.  He  has  always  insisted  that  transplanted 
tumors  represented  only  the  second  stage  in  the  development  of 
cancer  —  that  of  mahgnant  grQwth.  Because  in  spontaneous  neo- 
plasms this  secondary  period  was  preceded  by  a  transformation  of 
normal  cells  into  mahgnant  elements,  it  was  to  the  earlier  stage  that 
research  should  be  devoted,  and  especial  attention  had  accordingly 
been  bestowed  upon  the  youngest  tumors  in  the  study  of  his  own 
material. 

Cysts  were  not  uncommonly  found  among  mice  in  the  groin  or 
axilla,  both  of  which  were  sites  of  election  for  the  biting  insects.  In 
these  cysts,  or  in  the  connective  and  glandular  tissue  surrounding 
them,  Borrel  could  frequently  discover  Cestodes  or  Nematodes,  and 
these  helminths  seemed  to  be  without  doubt  a  causative  factor  in 
the  production  of  the  lesions.  In  the  connective  tissue,  muscles,  or 
capillaries  adjoining  young  adeno-carcinomata,  he  had  also  succeeded 
in  demonstrating  nematodes,  and  in  a  minute  tumor  had  found  the 

'  Ann.  de  I'Inst.  Past.,  1903,  xvii,  113. 
^  Bull,  de  rinst.  Past.,  1907,  v,  497. 
Travaux  de  la  deuxieme  Conference  internal,  pour  V Etude  du  Cancer,  Paris,  191 1,  193. 


196  THE    SPONTANEOUS   TUMOR 

trail  of  such  an  organism,  with  the  parasite  lying  at  the  end  of  it. 
Similar  worms  had  been  discovered,  moreover,  in  the  Imig  and  the 
lymph  nodes  of  its  hilum,  as  well  as  in  the  circulation  of  mice  suffer- 
ing from  generaHzed  lymphomata,  but  he  had  not  yet  thoroughly  ex- 
amined normal  mice  for  their  presence.  While  the  temptation  was 
great  to  consider  the  nematodes,  introduced  by  biting  insects,  as  the 
carriers  of  a  virus,  their  relation  to  malignant  growth  could  be  no 
more  than  suggested. 

It  was  possible,  however,  to  express  greater  certainty  in  the  case 
of  sarcoma  of  the  liver  in  rats.  Four  years  ago  he  had  reported  a 
rat  cancer  propagable  through  three  generations,  and  had  attributed 
the  growth  to  the  cysticercus  of  Taenia  crassicola,  while  in  another 
case  there  had  been  discovered  a  tiny  adeno- carcinoma  of  the  kidney 
developing  about  a  cysticercus.  Similar  cases  have  been  reported  by 
Regaud,^  Saul,"  Bridre,^  and  by  Bridre  and  Conseil.* 

But  not  only  were  endoparasites  found  in  connection  with  malig- 
nant growths.  Certain  ectoparasites,  as  the  Acaridae,  might  be  at 
fault,  and  in  the  mouse,  for  example,  there  was  recognized  a  cutaneous 
affection  which  was  distinguished  by  warty  excrescences  upon  various 
parts  of  the  body.  In  the  early  stages  of  this  disease,  an  adenomatous 
condition  of  the  sebaceous  glands,  there  could  be  discovered  a  still 
unidentified  mite.  These  organisms,  furthermore,  played  an  impor- 
tant role  in  the  lympho- sarcoma  of  dogs,^  and  one  of  them,  the  De- 
modex,  was  connected  with  cancer  of  the  face  in  man.  While  an 
infection  with  such  insects  was  frequently  present  in  the  nipples  of 
cancerous  women,  Borrel  did  not  wish  to  draw  any  conclusions 
regarding  the  relation  of  the  parasite  to  cancer  of  the  breast,  and 
pointed  out  that  the  great  majority  of  healthy  persons  would  present 
the  demodex  in  certain  portions  of  the  skin  —  perhaps  hundreds  to 
the  square  centimeter.     Various  authors  had  wrongly  ascribed  to  him 

^  Compt.  rend.  Soc.  Biol.,  1907,  Ixii,  194. 

^  Centralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1909,  xlix,  80. 

Berl.  klin.  Woch.,  1911,  xlviii,  341. 

Deut.  med.  Woch.,  1911,  xxxvii,  233. 

*  Compt.  rend.  Soc.  Biol.,  1909,  Ixvi,  376. 

*  Bull,  de  V Assoc,  franq.  pour  V Etude  du  Cancer,  1909,  ii,  171. 
Bidl  de  V Assoc,  franq.  pour  VEtude  du  Cancer,  1910,  iii,  318. 

^  Compt.  rend,  de  I' Acad,  des  Sc,  1907,  cxliv,  344. 


THE    SPONTANEOUS    TUMOR  197 

the  h}"pothesis  that  such  organisms  as  these  were  the  parasites  of 
cancer,  although  he  actually  believed  that  they  acted  only  as  carriers 
of  a  virus.  Because  a  nail  occasionally  produced  tetanus,  one  would 
never  think  of  describing  it  as  the  parasite  of  that  disease ;  it  was 
merely  that  the  bacillus  causing  tetanus  was  able  to  develop  after 
having  been  carried  into  the  tissues  by  the  foreign  body. 

Attention  was  directed  by  Loeb  and  Jobson  ^  to  a  ranch  in  Wyoming, 
upon  which  there  had  been  discovered  one  or  two  cases  of  carcinoma 
of  the  inner  canthus  of  the  eye  every  year  for  the  past  ten  years, 
among  two  thousand  head  of  cattle.  This  incidence  was  fifty 
times  greater  than  the  average,  and  the  similarity  of  the  tumors 
in  respect  of  character  and  location  was  remarkable.  The  animals 
on  the  neighboring  ranches  were  free  from  carcinoma. 

MichaeHs  -  mentioned  a  dealer  who  had  found  five  tumors  arising 
successively  among  the  mice  of  a  single  cage.  The  last  two  of  these 
growths  were  examined,  and  proved  to  be  maHgnant  adenomata. 

Gaylord  and  Clowes^  reported  that  in  the  spring  of  1902  there  were 
brought  to  the  State  Cancer  Laboratory  in  Buffalo  a  number  of  rats 
inoculated  with  a  cystic  sarcoma  of  the  thyroid,  and  that  for  the 
accommodation  of  these  animals  two  large  cages  and  a  number  of 
smaller  ones  were  constructed.  For  a  certain  period  of  time  these 
cages  contained  numbers  of  successfully  inoculated  rats,  but  from 
December,  1902,  until  the  summer  of  1903,  they  were  empty.  During 
and  after  the  summer  of  1903  the  large  cages  were  again  put  to  use, 
and  a  year  later  one  of  the  rats  kept  in  them  developed  a  fibro-sarcoma. 
Eight  others  were  accordingly  placed  in  this  cage,  while  into  the  second 
one  there  were  put  six  or  eight  more.  Four  months  later  the  two 
sur\dving  males  in  the  first  cage  had  developed  tumors,  one  of  which 
was  a  cystic  spindle  cell  sarcoma  of  the  thyroid,  the  other  a  fibro- 
sarcoma. No  tumors  appeared  either  among  the  inmates  of  the 
control  cage  or  of  the  other  cages  in  the  laboratory  although  there 
were  no  less  than  one  hundred  rats  on  hand,  nor  did  any  develop 
among  the  animals  in  the  smaller  cages,  which  had  been  sterilized. 

1  Jour.  Comparative  Med.  and  Yet.  Archiv.,  1900,  xxi,  3SS.  See  also  Loeb,  Arch.f.  kiln. 
Chir.,  (v.  Langenbeck),  1903,  Ixx,  S45,and  Centralbl.  f.Bakt.,  etc.,  erste  Abt.,  Orig.,  1904, 
x.xxvii,  236. 

^  Zeitschrijt  J.  Krcbsforsch.,  1906,  iv,  2.      ^  Jour.  American  Med.  Assoc.,  1907,  xlviii,  15. 


198  THE    SPONTANEOUS   TUMOR 

A  second  observation  by  the  same  authors  related  to  the  endemic 
occurrence  of  cancer  among  mice.  There  was  discovered  in  the  pos- 
session of  a  dealer  a  cage  in  which  about  sixty  spontaneous  tumors 
had  occurred  in  the  course  of  three  years.  The  location  of  this  cage 
had  been  changed  frequently  and  the  stock  had  been  entirely  re- 
moved on  at  least  one  occasion.  The  dealer  was  of  the  impression 
that  most  of  the  affected  mice  had  been  females,  and  added  that  he 
had  never  seen  a  tumor  on  the  back  of  a  mouse. 

Balancing  these,  and  many  similar  observations,  stands  the  following 
quotation  from  Bashford  ^ :  "...  alleged  epidemics  have  often  been  re- 
corded in  .  .  .  mice  and  rats  housed  together  in  small  cages.  Satis-" 
factory  proof  that  these  aggregations  of  cases  were  due  to  infection  has 
not  been  furnished,  and  the  alternative  explanation,  that  they  arise 
as  the  result  of  in-breeding  cancerous  stock,  has  naturally  sug- 
gested itself.  Our  very  detailed  observations  on  tens  of  thousands 
of  mice  have  not  revealed  in  our  laboratory  anything  which  we 
would  call  an  epidemic.  When,  however,  we  take  into  consideration 
the  manner  in  which  cases  of  carcinoma  mamm«  have  been  sent  to 
us  by  breeders  we  find  the  same  kind  of  e\ddence  as  that  which  has 
led  observers  in  France,  America,  and  Germany  to  assert  that  epi- 
demics of  cancer  occur  in  breeding  establishments.  We  may  illustrate 
this  kind  of  evidence  by  the  numbers  of  tumour-mice  sent  in  by  four 
of  the  breeders  who  supply  us  with  mice,  under  a  guarantee  that 
no  fresh  stock  has  been  introduced.  From  January  i,  1906,  to 
October  31,  1907,  Mr.  A  sent  us  ten  cases,  Mr.  B,  six  cases,  Mr.  C, 
thirty-five  cases,  and  Mr.  D,  eighteen  cases  of  carcinoma  of  the  mamma. 
These  figures,  which  are  more  remarkable  than  any  others  yet  pub- 
Hshed,  are  no  evidence  that  there  was  an  endemic  or  epidemic  occur- 
rence of  cancer  in  the  breeding-cages  of  Mr.  C  or  ]\Ir.  D.  The 
proportions  of  mice  supphed  to  us  in  the  same  period  to  cases  of 
cancer  were   as  follows  :  — 

Mice  with  Tumour  Total  Mice 

"Mr.  A 10 1,302 

Mr.  B 6' 1,547 

Mr.  C 35     ... 9,698 

Mr.  D 18    . 11,842 

^  Proc.  Roy.  Soc.  Med.,  1909,  ii,  General  Reports,  72. 


'the  spontaneous  tumor  199 

"The  numbers  of  tumours  occurring  in  these  stocks  of  mice  have  been 
determined  solely  by  the  number  of  mice  of  'cancer  age'  under  obser- 
vation. This  is  brought  out  particularly  clearly  in  the  difference 
between  the  age  constitution  of  the  stock  of  Mr.  C  and  Mr.  D,  since 
the  stock  of  the  latter  contains  constantly  a  much  higher  proportion 
of  young  animals,  and  he  supplies  us  with  most  of  our  young  mice. 
Further,  if  we  note  the  dates  on  which  tumours  are  sent  to  us  and 
arrange  them  in  columns,  we  find  that  the  crops  of  tumours  coincide 
with  the  ageing  of  groups  of  mice.  Thus  those  apparent  aggregations  of 
cases,  wrongly  called  epidemics  by  too  enthusiastic  advocates  of  a  para- 
sitic origin  for  cancer,  also  give  no  indication  of  haphazard  in-breed- 
ing leading  to  a  preponderance  of  cases  of  cancer  of  the  mamma.  The 
incidence  of  the  disease  for  mice  continues  to  obey  the  laws  of  age-  and 
sex-distribution,  even  where  in-breeding  is  proceeding  haphazard." 

Influence  of  Age  and  Sex 

Most  investigators  are  agreed  that  spontaneous  malignant  tumors 
are  much  more  common  in  female  than  in  male  mice,  that  the  most 
frequent  site  is  the  mammary  gland,  that  the  tumors  are  nearly  always 
of  epithelial  origin,  and  that,  as  in  man,  age  plays  an  important  part 
in  preparing  the  animals  for  their  inception. 

Malignant  growths  are  found  in  the  mouse  with  comparative  fre- 
quency if  they  are  sought,  and  whereas  in  1905  Bashford,  Murray, 
and  Cramer^  had  been  able  to  discover  but  twelve  among  nearly 
thirty  thousand  tame  mice  of  all  ages,  Murray,^  six  years  later,  re- 
corded 8.6  %  in  two  hundred  and  twenty-three  females  of  non-cancer- 
ous ancestry,  and  of  all  ages  from  six  months  upward. 

Apolant,^  among  two  hundred  and  twenty-one  tumor  mice  (two 
hundred  and  seven  white  and  fourteen  gray),  found  two  hundred  and 
seventy- six  growths,  thirty-eight  of  the  mice  having  from  two  to  five 
each,  while  in  confirmation  of  observations  previously  published  with 
Ehrhch  "^  not  a  single  case  had  occurred  in  a  male.     Among  these  two 

^  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  15. 
&     ^  Proc.  Roy.  Soc,  Series  B,  igii-1912,  Ixxxiv,  42. 

Fourth  Set.  Report,  Imperial  Cancer  Research  Fund,  London,  191 1,  129. 
'  Arb.  a.  d.  Konigl.  Inst.  f.  E.xp.  Therap.,  1906,  Heft  i,  15. 
*  Berl.  klin.  Woch.,  1905,  xlii,  872. 


200  THE    SPONTANEOUS    TUMOR 

hundred  and  seventy-six  tumors,  two  hundred  and  thirty-three  of 
which  were  examined  and  found  to  be  epithehal,  two  hundred  and 
fifty-nine  were  on  or  near  the  ventral  surface  of  the  body. 

Among  two  hundred  and  eighty-eight  tumor  mice,  according  to 
Haaland,^  only  six  were  males,  and  of  the  three  hundred  and  fifty- 
three  tumors  detected  in  these  mice,  three  hundred  and  eleven  pre- 
sented the  structure  of  mammary  adeno- carcinoma. 

Influence  of  Lactation 

Apolant  ^  was  struck  by  the  fact  that  tumors  in  the  mouse  were 
found  most  often  in  an  organ  of  very  vigorous  functional  energy. 
That,  in  contrast  to  man,  a  single  organ  should  be  so  uniformly  affected, 
he  thought  might  be  partly  explained  by  the  injuries  inseparable  from 
physiological  acti\dty.  This  interpretation  has  been  discounted  con- 
,siderably,  however,  by  the  later  observations  of  Haaland." 

"Of  74  mice  which  had  developed  mammary  tumours,  and  which 
were  under  observation  from  birth,  only  33  are  recorded  to  have 
Httered  previously  to  the  development  of  the  tumour,  while  no  fitter 
is  recorded  for  41.  .  .  .  Of  the  33  ha\dng  fittered  pre\dously  to  the 
development  of  the   tumour :  — 

"  I  fitter  is  recorded  in  11  cases 


2fi 

tters 

are    '" 

/ 

3 

ii 

(C 

7     " 

4 

u 

cc 

" 
5 

5 

a 

a 

2     " 

7 

Cl 

a 

I  case 

"The  figures  show  that  it  is  hardly  likely  that  excessive  physio- 
logical demands  made  upon  the  mamma  play  the  determining  role 
in  the  development  of  tumours  of  this  organ,  but  that  other  factors 
must  be  looked  for." 

Influence  of  Heredity 

One  aspect  of  the  investigation  of  cancer  to  which  the  mouse  lends 
itself  most  readily  is  that  concerning  the  relation  of  heredity  to  the 

'^Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1911,  9. 

2  Arh.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  40. 

^Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  191 1,  43. 


THE    SPONTANEOUS   TUMOR  20I 

occurrence  of  spontaneous  tumors,  and  this  because  mice  rarely  live 
to  be  over  two  years  old.  The  diificulty  of  settling  the  question  in  man 
is  well  illustrated  by  a  paragraph  from  Newsholme  :  ^  — 

"The  fact  that  several  members  in  successive  generations  of  a  given 

family  have  died  from  cancer  is  commonly  accepted  as  proof  that  the 

disease  is  hereditary.     This  is  far  from  being  the  case.     Cancer  causes 

a  certain  average  number  of  deaths  among  a  given  number  of  persons. 

.  .  .     Given  a  certain  probabiKty  of  death  from  cancer,  and  knowing 

the  number  of  a  family,  it  is  easy  to  calculate  the  probability  of  one, 

two,  or  more  of  them  dying  of  cancer,  quite  independently  of  heredity. 

Even    if    heredity  were  proved   to  be   absolutely  inoperative,   it  is 

certain  that  there  would  be  famihes  among  whom  numerous  deaths 

from  cancer  would  occur.     It  does  not  prove  heredity  to  show  that 

in  one  family  five  deaths,  say,  occurred  from  cancer.      This  might 

happen  from  mere  chance,  and  in  fact,  such  cases  must  occur  without 

heredity  at  all.     De   Morgan  worked  out   the  probabihty  of   looo 

successive  heads  being  thrown  in  tossing  a  coin,  and  he  showed  that 

given  a  sufificient  number  of  people  starting  to  toss  coins,  it  was  a 

certainty  that  at  least  one  of  them  would  toss  looo  consecutive  heads. 

So,  given  a  sufficient  number  of  families,  it  is  a  certainty,  even  if  there 

be  no  such  thing  as  heredity,  that  of  at  least  one  family,  say  ten 

members  v^^ill  die  of  cancer.     The  only  absolute  proof  of  heredity 

would  be  to  show  that  cancer  occurred  frequently  in  certain  families, 

and  practically  nowhere  else ;   short  of  this  the  probability  of  heredity 

of  cancer  would  be  increased  if  it  could  be  shown  that  cancer  was 

much  more  common  in  certain  famihes  than  in  the  average  for  the 

whole  community,  due  allowance  being  made  for  variations  in  age  and 

sex-distribution." 

The  suitabihty  of  the  short-Uved  domestic  animals  for  the  investi- 
gation of  problems  in  heredity  was  indicated  by  Bashford,^  who  re- 
ported later  ^  that  after  three  years  of  failure  he  had  been  able  to  obtain 
offspring  from  mice  with  spontaneous  cancer,  and  expressed  the  hope 
that  data  relating  to  the  existence  of  hereditary  susceptibility  might 
be  obtained  in  time.  In  the  following  year  '^  breeding  experiments 
were  well  under  way,  and  by  crossing  spontaneously  affected  animals 

1  The  Elements  of  Vital  Statistics,  London,  1899,  248.     ^  British  Med.  Jour.,  1903,  ii,  128. 
^  BritishMed.  Jour.,  1906,  ii,  207.  ^British  Med.  Jour.,  1907,  ii,  27. 


202 


THE    SPOXTAXEOUS    TUMOR 


with  the  offspring  of  cancerous  parents,  strains  of  mice  were  being 
obtained  in  which  the  cancerous  heredity  was  one-hah",  three-fourths, 
fifteen-sixteenths,  or  even  higher. 

A  prehminarj^  account  of  these  experiments  was  given  by  Bashford 
and  Murray/  and  a  completer  analysis,  founded  on  more  extended  ob- 
servation, by  Murray.-  The  follo-^ing  table,  abbreAdated  from  Mur- 
ray's, shows  the  ratio  of  deaths  from  cancer  to  deaths  from  all  causes, 
among  five  hundred  and  sixty-three  ^  mice  of  a  highly  inbred  stock 
with  a  heredity  more  or  less  cancerous,  the  figures  referring  to 
females  only.  The  table  "...  shows  a  rapidly  increasing  proportion 
of  deaths  from  cancer  commencing  after  sLx  months  is  passed,  and 
attaining  a  maximum  in  the  three-monthly  period  ending  at  i8  months. 
In  the  succeeding  periods  the  frequency  diminishes,  till  in  mice  over 
24  months  old  the  frequency  is  barely  t\^dce  that  found  in  mice  under 
9  months  old.  Similar  figures  for  the  human  female  give  a  cor- 
responding curve." 

TABLE   I  {after  Murray) 


Age  (months)      .     . 

^3 

-6 

-9 

-12 

-IS 

-18 

1 
-21      -24 

Over 

24 

TOT.\L 

Total  mice 

— 

— 

100 

104 

88 

94 

69 

55 

53 

563 

Percentage  of 
mammar}'  cancer 

— 

— 

5-0 

10.6 

18.2    28.0 

14-5 

14.0 

9.4 

14.4 

The  five  hundred  and  sixty-three  mice  were  then  distributed 
into  two  groups.  The  first  contained  three  hundred  and  forty 
mice  of  recent  cancerous  ancestry,  of  which  the  mother,  one 
or  both  grandmothers,  or  all  three  had  been  cancerous.  To  the 
second  were  assigned  two  hundred  and  twenty-three  mice  of  remote 
cancerous  ancestry — mice,  that  is.  where  no  cancer  had  occurred  in 

^  Proc.  Roy.  Soc,  Series  B,  1909,  Ixsxi,  310. 

'^  Proc.  Roy.  Soc,  Series  B,  1911-1912,  Ixxxiv,  42. 

Fourth  Set.  Report,  Imperial  Cancer  Research  Fund,  London,  191 1,  114. 
^  Through  a  clerical  error  the  total  was  given  in  Murray's  paper  as  five  hundred  and 
sixty-two. 


THE    SPONTANEOUS    TUMOR 


203 


either  the  mothers  or  the  grandmothers.  The  majority  of  the  cases 
of  cancer  occurred  in  the  members  of  the  first  division,  as  may  be 
seen  from  tables  II  and  III  (abbreviations  of  Murray's)  which  show 
the  percentage  of  cases  occurring  in  the  first  and  second  groups  respec- 
tively. 

TABLE   II  {after  Murray) 


Age  (months)      .     . 

0-3 

-6 

-9 

-12 

-15 

-18 

-21 

-24 

Over 

24 

Total 

Total  mice     .     .     . 

— 

— 

62 

63 

62 

56 

40 

29 

28 

340 

Percentage  of 

mammary  cancer 

— 

6.5 

II. I 

24.2 

32.1 

25.0 

17.2 

10.7 

18.2 

TABLE   III  {after  Murray) 


Age  (months)     .     . 

0-3 

-6 

-9 

-12 

-IS 

-18 

-21 

-24 

Over 

24 

Total 

Total  mice     .     .     . 

— 

— 

38 

41 

26 

38 

29 

26 

25 

223 

Percentage  of 
mammary  cancer 

— 

k 
2.6 

9.8 

3.8 

21.6 

0,0 

"•5 

8.0 

8.6 

The  figures  were  submitted,  further,  to  mathematical  analysis  in- 
volving a  determination  of  the  standard  errors  of  the  differences  be- 
tween the  cancerous  and  non-cancerous  groups .  Taking  the  crude  data, 
the  actual  percentages  amongst  all  the  offspring  were  :  — 

Ancestry  cancerous 18.2% 

Ancestry  non-cancerous 8.6% 

When  a  correction  was  made  for  the  varying  age-distributions  of  the 
two  groups  by  calculating  corrected  percentages  based  on  the  age- 
distribution  of  all  mice  as  a  standard,  and  reducing  the  numbers  for  the 
five  hundred  and  sixty-three  mice  to  the  corresponding  proportions 
per  thousand,  the  difference  was  increased  only  from  9.6  to  9.8%. 
As  the  standard  error  of  this  difference  was  2.96,  the  difference  was  3.3 


204  THE    SPONTANEOUS   TUMOR 

times  the  standard  error,  and  the  chance  of  its  occurring  as  a  mere 
fluctuation  of  random  sampHng  only  about  one  in  a  thousand. 

Murray  thought,  therefore,  that  the  disparity  between  the  two  groups 
was  not  due  to  chance  but,  on  the  contrary,  almost  certainly  signifi- 
cant, and  that  the  increased  Hability  was  probably  in  the  nature  of  a 
predisposition  of  one  particular  tissue  or  organ  system  to  undergo 
cancerous  transformation  under  the  wear  and  tear  of  Hfe.  The  differ- 
ence between  the  two  series  was  apparent  at  all  ages,  and  the  age  of 
maximum  incidence  did  not  appear  to  have  been  lowered  in  the  predis- 
posed group. 

In  discussing  the  application  of  these  results  to  man,  Bashford  ^ 
extended  a  warning  against  too  pessimistic  conclusions,  pointing 
out  that  the  influence  of  heredity  had  been  demonstrated  only  for  stocks 
where  this  factor  had  been  concentrated  by  careful  mating.  Such  a 
concentration  could  occur  in  man  only  by  hazard  as  a  coincidence  of 
considerable  rarity,  and  it  was  probable  that  the  influence  of  heredity 
in  the  general  population  was  manifested  as  an  average  predisposition 
of  low  intensity. 

Meanwhile  the  question  had  been  approached  by  Tyzzer,^  who 
called  attention  to  the  relative  frequency  of  growths  in  the  descen- 
dants of  those  mice  which  had  fallen  prey  to  mahgnant  tumors.  The 
number  which  had  occurred  in  three  families  derived  from  three  female 
mice  with  spontaneous  growths  indicated  that  tumor  development 
was  influenced  by  inherited  quahties. 

Murray,^  without  wishing  to  minimize  the  value  of  Tyzzer's  careful 
work,  indicated  that  the  neoplasms  recorded  by  that  author  belonged 
mainly  to  types  in  which  the  maUgnancy  was  not  very  pronounced. 
The  majority  of  the  tumors  were  cyst-adenomata  of  the  lung,  a  vari- 
ety which  it  would  be  hazardous  to  regard  in  all  cases  as  mahgnant^ 
and  the  multiple  lymphomata,  which  were  second  in  frequency,  could 
not  be  separated  satisfactorily  from  conditions  resembling  diffuse 
hyperplasia,  although  the  type  did  include  new  growths  of  undoubted 


^  Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  igii,  Introduction,  p.  xvi. 
2  JoiiT.  Med.  Research,  1907-1908,  N.S.,  xii,  199. 
Jour.  Med.  Research,  1909,  N.S.,  xvi,  479. 
^  Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  191 1,  115. 


J.  R.  Ford.  del. 

Hypertrophic  mairLmar>-  nodule.  Increased  number  of  acini,  on  the  whole  of  fairly  normal  appearance, 
with  increased  cellularitj'  of  the  stroma.  Concretions  in  the  lumina.  At  one  point  the  acini  have 
assumed  atypical  forms,  and  there  are  signs  of  pressure  in  the  surrounding  tissues.  Xo  other  sign 
of  active  growth.     X  -i-. 


J.  R.  Ford.  del. 

H\-pertrophic  mammary  nodule  from  another  mouse.  The  epitheliimi  of  the  acini  is  distinctly  atypi- 
cal, in  that  the  cells  are  larger  than  normal  and  more  crowded,  so  that  several  layers  are  found 
lining  some  acini.  This  appearance  is  not  due  to  obliquity  of  the  section.  A  few  mitoses  are 
discoverable.     X  -f^. 


THE    SPONTANEOUS    TUMOR 


205 


malignancy.  Furthermore,  while  cyst-adenomata  of  the  lung  oc- 
curred in  males  and  females  with  equal  frequency,  multiple  lympho- 
mata  had  been  found  among  Tyzzer's  material  much  more  often  in 
females,  and  a  serious  source  of  error  was  introduced  when  the  fre- 
quency of  tumors  as  a  whole  was  reckoned  on  males  and  females 
together. 

Jensen  ^  was  able  to  bring  to  maturity  among  the  descendants  of  a 
cancerous  female  about  fifty  mice  in  four  or  five  generations,  none  of 
which,  however,  developed  a  tumor.  Another  mouse  with  spontaneous 
cancer  bore  four  young,  one  of  which  developed  an  enormous  intra- 
abdominal round  cell  sarcoma.  Two  males  of  this  litter  used  for 
breeding  gave  rise  to  four  or  five  hundred  descendants  in  six  or  seven 
generations,  and  even  though  many  of  their  offspring  died  at  an  early 
age  during  epidemics,  several  tumors  of  the  usual  type  developed 
among  them. 

Influence  of  Inflammation 

Haaland,^  in  trying  to  account  for  the  multicentric  origin  of  mam- 
mary tumors  in  mice,  examined  serial  sections  of  the  mammae  in  both 
cancerous  and  non-cancerous  animals.  The  normal  condition  of  this 
gland  after  the  era  of  physiological  activity  had  passed  appeared  to  be 
one  of  more  or  less  atrophy,  acQompanied  by  sclerotic  changes  in  the 
connective  tissue  and  arteries.  Chronic  inflammation  of  the  inter- 
stitial tissue,  either  diffuse  or  locaHzed,  was  very  common,  as  was  dila- 
tation of  the  ducts  with  its  consequent  cyst  formation.  The  epithe- 
lium bounding  these  cavities  was  usually  that  of  the  normal  duct  or 
acinus  flattened  by  pressure  of  the  contents,  although  occasionally 
the  cysts  were  fined  by  epithefial  cells  of  the  squamous  type. 

In  addition  to  the  lesions  just  mentioned,  all  stages  of  nodular 
hypertrophy  of  the  mammary  epithefium  were  met  with,  varying  from 
a  sfight  increase  in  the  number  of  normal  acini  in  one  lobe,  to  the 
formation  of  definite  nodules.  All  gradations  might  exist  between  this 
condition  and  mafignant  growth,  and,  indeed,  there  were  times  when  it 
was  impossible  to  decide  between  the  two.  The  frequent  association  in 
the  same  gland  of  all  degrees  of  nodular  hypertrophy  with  veritable 

^  Zeitschrift  f.  Krebsforsch.,  1908-1909,  vii,  285. 

2  Fourth  Sci.  Report,  Imperial  Cancer  Research  Fmid,  London,  191 1,  30. 


2o6 


THE    SPONTANEOUS   TUMOR 


new  growths,  made  it  probable  that  the  lesion  bore  some  relation  to 
tumor  development,  and  it  was  intimated  that  the  nodes  might  be 
either  the  base  upon  which  cancerous  proliferation  started,  or  true 
tumors  from  their  very  inception.     While  nodular  hypertrophies  were 


Fig.  io. —  Multiple  minute  hypertrophic  nodules  in  the  mammEe,  reflected  with 
the  skin.  The  figure  also  represents  the  zone  free  from  mammary  gland,  chosen  for 
autologous  inoculation. 

found  most  commonly  in  mice  with  cancer  in  another  mamma,  Haaland 
proved  that  they  were  not  secondary  deposits  by  demonstrating  in 
serial  sections  their  normal  connection  with  the  mammary  ducts. 
The  inflammatory  and  sclerotic  conditions  in  the  connective  tissue 
were  important  because  many  cases  of  tumor  development  sug- 
gested that  the  process  had  taken  place  in  an  organ  diffusely  diseased, 
and,  moreover,  because  the  nodular  h>TDertrophy  just  discussed  was 


K 


^^1 


J.  R.  Ford.  del. 

Stretched  and  stained  subcutaneous  tissue  of  old  normal  female  mouse.     A  nematode  is  seen,  con';ainin| 
large  embryos;  five  extruded  embr\^os  in  the  subcutaneous  tissue  at  a  considerable  distance  fromi 
the  mother  worm.     X  ^  . 


c? 


r,"^2a. 


J.  R.  Ford.  del. 

Oblique  section  of  a  nematode  embryo   free  in  the  interstitial  mammar}'  tissue  of  an  old  normal 

female  mouse.     X  ^^ 


THE    SPONTANEOUS   TUMOR 


207 


a  process  too  far  advanced  to  be  investigated  setiologically.  It  was 
therefore  necessary  to  examine  the  mammary  glands  of  old  non-can- 
cerous mice.  When  this  was  done,  inflammatory  changes  in  the  con- 
nective tissue  were  discovered  to  be  of  common  occurrence,  and  often 
associated  with  the  presence  of  nematodes,  such  as  had  previously 
been  found  by  Borrel  in  young  tumors  and  their  surroundings,  and  in 
the  lungs,  mammae,  and  mediastinal  lymph  nodes  of  tumor-bearing 
mice. 

In  his  own  cases,  Haaland  detected  the  parasites  in  the  subcutaneous 
tissue  of  a  large  proportion  of  old  normal  mice  from  different  breeders, 
in  addition  to  finding  them,  also,  in  the  pulmonary  vessels  and  once 
in  the  pleura.  They  were  usually  few  in  number  and  discoverable 
only  after  long  search,  although  as  many  as  half  a  dozen  or  more  had 
been  found  in  one  mamma.  The  worms  were  all  females  containing 
large  numbers  of  eggs  or  embryos,  and  the  possibility  of  liberation  of 
the  latter  in  the  subcutaneous  tissue  was  demonstrated  by  their  dis- 
covery in  that  location. 

That  the  nematodes  were  capable  of  setting  up  an  intense  inflamma- 
tion was  shown,  not  only  by  the  zone  of  leucocytes  surrounding  areas 
where  they  had  remained,  alive,  for  some  time  (encapsulated?),  but 
by  still  other  signs  marking  thei^  path.  When  they  lay  dead  in  the 
tissues  a  vigorous  leucocytic  and  lymphocytic  reaction  supervened, 
and  phagocytosis  proceeded  until  the  worm  finally  became  unrecog- 
nizable. 

These  characteristic  lesions  accompanying  the  parasites  affected 
the  loose  connective  tissue  alone,  and  the  mammary  gland  was  involved 
only  indirectly  and  in  so  far  as  it  was  embedded  on  all  sides  in  this 
tissue.  In  several  instances  the  inflammatory  condition  co-existed 
with  nodular  hypertrophy,  an  association  which  suggested  that  the 
two  might  be  connected  and  referred  to  a  common  cause  —  the  pres- 
ence of  nematodes  in  the  subcutaneous  tissue.  In  half  a  dozen 
males  examined,  the  worms  were  found  in  the  same  proportion  as 
in  females,  while  evidence  from  young  or  adult  mice  was  still  scanty. 

The  observations  of  Murray  ^  on  carcinoma  of  the  liver  in  cows 
gain  an  enhanced  interest  in  connection  with  Haaland's  remarks. 
These  growths  Murray  found  very  common,  and  almost  invariably  asso- 

1  Veterinary  News,  1910,  vii,  563, 


2o8  THE    SPONTANEOUS   TUMOR 

dated  with  a  severe  biliary  cirrhosis  due  to  infection  with  the  Distoma 
hepaticum.  The  new  growths  did  not  arise  in  the  bile  ducts,  however, 
but  in  the  parenchyma,  and  the  irritation  of  the  parasites  acted  only 
as  an  indirect  cause. 

The  observations  of  both  authors  together  are  of  further  significance 
when  taken  in  conjunction  with  the  well-known  frequency  of  epithe- 
lial growths  of  the  rectum  and  bladder  of  man  in  the  presence  of  in- 
fection with  the  Bilharzia  haematohia. 

^Etiology  Theoretically  Considered 

Ehrlich  ^  advanced  the  following  explanation  of  malignant  growth, 
couched  in  terms  of  the  side-chain  theory.  The  division  of  nutrient  ma- 
terial throughout  the  body  was  regulated  by  the  number  of  receptors 
possessed  by  the  various  cells,  as  well  as  by  the  avidity  of  these 
receptors,  so  that  immoderate  growth,  like  that  of  a  tumor  cell,  could 
be  achieved  only  through  equipment  with  receptors  having  an  avid- 
ity for  foodstuffs  relatively  higher  than  the  normal.  When,  as  often 
happened,  a  primary  tumor  of  the  mouse  was  implanted  unsuccess- 
fully into  hundreds  of  other  mice,  this  failure  could  mean  only  that 
the  receptors  of  the  transplanted  tumor  cells  possessed  an  avidity  no 
higher  than  the  average  obtaining  in  the  cells  of  these  mice.  Hence 
the  origin  of  a  growth  must  be  conditioned,  not  by  an  increase  in  the 
avidity  of  its  own  cells,  but  by  a  general  lowering  of  that  of  the 
receptor  apparatus  of  the  entire  body,  and  the  tumor  cells  possessed, 
therefore,  a  relatively  but  not  an  actually  higher  avidity  than  the 
normal  cells  of  the  organism. 

The  growth  of  a  transplantable  tumor  in  normal  mice  was,  however, 
in  the  opinion  of  Murray,-  more  a  result  of  the  adaptability  of  its  cells 
to  new  surroundings.  He  found  that  tumors  transplanted  into  sponta- 
neously affected  animals  which  had  been  relieved  by  operation  became 
established  in  consequence  of  a  great  power  to  accommodate  them- 
selves in  new  hosts,  and  that  they  shared  the  food  supply  in  common 
with  the  normal  tissues  without  starving  them.     When  a  spontaneous 

^  Zeitschrift  f.  aerztliche  Fortbildung,  1906,  iii,  210. 

Arh.  a.  d.  Konigl.  Inst.  f.  Exp.  Therap.,  1906,  Heft  i,  86. 
^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  108. 


THE    SPONTANEOUS   TUMOR  209 

growth  recurred  it  increased  in  size  more  rapidly,  as  a  rule,  than  did 
the  transplanted  tumor,  even  though  its  energy  of  growth  (as  tested 
by  inoculation  into  normal  animals)  was  much  inferior  to  that  of  the 
propagable  neoplasm.  This  would  be  quite  inexplicable  on  the  as- 
sumption that  a  difference  in  avidity  for  food  was  the  factor  princi- 
pally determining  their  relative  rates  of  proliferation,  but  became  at 
once  intelligible  when  the  importance  of  adaptability  was  considered. 
The  recurrent  spontaneous  tumor  was  in  its  native  environment  and 
the  food  materials  presented  to  it  were  those  to  which  it  had  always 
been  accustomed,  wherefore  adaptation  was  not  required,  and  suc- 
cessful competition  with  a  transplantable  growth  was  possible. 

The  relation  of  a  spontaneous  growth  to  the  animal  bearing  it  could 
not  be  described  so  simply  as  Ehrlich  had  supposed,  merely  by  postulat- 
ing a  different  avidity  for  food  in  accordance  with  the  side-chain  theory. 
The  relative  affinities  for  nourishment  exhibited  by  normal  tissue  and 
tumor  must  remain  vaguely  speculative,  as  long  as  the  avidity  of 
malignant  cells  was  measured  solely  by  their  ability  to  grow  and  com- 
parisons made  with  normal  adult  cells  no  longer  engaged  in  active 
proliferation. 

Haaland  ^  exchanged  grafts  between  two  animals  spontaneously 
affected,  each  tumor  being  at  the  same  time  inoculated  into  its  bearer 
and  into  normal  mice.  In  the  course  of  these  experiments  two  can- 
croids were  transplanted  into  about  a  thousand  young  mice,  and  although 
six  hundred  and  eighty- six  of  them  lived  more  than  four  weeks,  growth 
did  not  take  place  in  a  single  instance.  According  to  EhrKch's  hypothe- 
sis, the  body  cells  of  the  spontaneously  affected  mice  in  which  tumors  of 
such  low  avidity  had  been  allowed  to  grow  should  be  possessed  of  a  still 
lower  degree  of  avidity,  and  such  animals  should  be,  in  consequence, 
more  susceptible  to  the  transplantation  of  other  tumors.  But  this  was 
not  the  case.  Grafts  were  exchanged  between  the  two  animals  in  which 
these  cancroids  arose,  but  no  growth  was  obtained  in  either ;  moreover, 
the  two  mice  were  refractory  even  to  a  tumor  of  higher  avidity. 
These  experiments,  and  others  of  a  similar  nature,  indicated  that  the  con- 
ditions for  tumor  growth  were  much  more  complex  and  specific  than 
could  be  explained  by  supposing  a  difference  of  avidities.  "The  condi- 
tions for  which  two  histologically  indistinguishable  tumours  are  adapted 

1  Fourth  Sci.  Report,  Imperial  Cancer  Research  Fimd,  London,  191 1,  62. 


2IO  THE    SPOXTAXEOUS    TUMOR 

are  so  different  that  they  can  be  only  very  rarely  exchanged  without 
the  mahgnant  mode  of  growth  ceasing  altogether."' 

Bashford  ^  represented  Ehrhch's  hypothesis  diagrammatically,  and 
discussed  the  question  as  follows  :  — 

''The  side-chain  theor}^  as  appHed  to  cancer,  if  stripped  of  its  special 
technical  terminology,  amounts  simply  to  assuming  that  the  cells  of 
some  malignant  new  growths  take  up  food-stufls  more  rapidly  and  more 
energetically  than  do  normal  tissues.  By  \-irtue  of  this  property  such 
tumours  can  be  transplanted  to  fresh  hosts  ;  once  estabhshed  and  grow- 
ing in  these,  such  tumours  can  prevent  a  secondary  inoculation  or  metas- 
tases from  growing  by  virtue  of  the  rate  with  which  food-stuffs  are 
■withdrawn.  A  subsidiary  assumption  is  made  that  this  starvation 
of  a  natural  or  artificial  metastasis  may  be  effected  by  deprivation  of 
special  tood-stuft's.  Great  importance  is  attached  to  the  assumption 
that  it  is  possible  to  increase  artificially  the  a\adity  of  the  tumour-cells 
for  food-stuffs ;  in  other  w^ords,  to  increase  the  rapidity  of  cell-division. 

"  Following  the  practice  observ^ed  in  the  Second  Scientific  Report, 
where  all  the  more  important  theories  of  cancer  were  diagram mati- 
cally  depicted,  Ehrlich's  hApothesis,  formulated  since  then,  may  also 
be  reduced  to  a  diagram  without  suggesting  that  he  would  approve  it 
as  correctly  reproducing  all  the  details  of  his  elaborate  argument. 

"A  number  of  lines  of  equal  length  may  represent,  as  in  the  accom- 
panpng  diagram,  the  normal  axddity  of  the  body.  Departures  from 
the  normal  may  be  depicted  by  other  fines  exceeding  or  faUing  short 
of  one  passing  through  the  tops  of  those  representing  the  normal. 
Thus  in  the  accompamdng  diagrams  (a)  and  (a')  will  represent  the 
normal  and  (b)  will  represent  the  simplest  departure  from  it,  namely, 
an  increased  aridity ;  but  this  assumption  requires  no  further  con- 
sideration, since,  if  it  were  true,  then  on  the  basis  of  Ehrfich's  h}'poth- 
esis  every  tumour  should  be  easily  transplanted  into  normal  animals. 
This  is  not  the  case,  and  Ehrlich  dismisses  this  assumption,  which 
was  put  forward  by  that  distinguished  pathologist,  the  late  Professor 
E.  Albrecht.  Instead  of  assuming  retention  of  normal  a\fidity  by  the 
body,  and  increased  a\'idity  by  the  tumour-cells,  Ehrfich  assumes  that  as 
a  rule  the  body-cells  lose  in  avidity  with  increasing  age  (b'),  (c),  (d), 
while  the  tumour  cefis  retain  the  normal  (b')  or  do  not  lose  it  in  a  degree 
1  Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1911,  188. 


THE    SPONTANEOUS    TUMOR 


211 


equal  to  that  lost  by  the  body  (c).  In  some  cases  it  is  assumed  that 
Albrecht's  view  (b)  may  hold,  or  that  while  the  body-cells  lose  in  avid- 
ity, the  tumour-cells  may  exceed  the  normal  (d),  and  it  is  further  as- 


increased  avidity. 


Normal  avidity, 

— IliiBS 


iMli 


(a)  (6) 

Diagrammatic  representation  of  Albrecht's  hypothesis. 


Increased  avidity. 


Normal  avidity. 


•  ■■■ 

I : 


::: 


•  • 


:; 


•  •• 

'■"■ 

'I' 
I  I 


1 1 


(a')  Normal 


{¥)  Transplantable 
IN  Low  Percentage 


(c)  Not  Trans- 
plantable 


(d)  Transplantable 
in  High  Percentage 


Fig.   II.  —  Diagrammatic  representation  of  Ehrlich's  hypothesis  as  deduced  by  him  from 
his  transplantation  experiments  on  mice. 


sumed  that  this  exaggerated  avidity,  when  not  present  at  the  first  trans- 
ference to  normal  animals  from  the  animal  in  which  the  growth  arose, 
can  be  artificially  induced  by  a  particular  experimental  procedure,  viz. 
artificial  selection  of  the  rapidly  growing  tumours  and  forced  passage. 


212 


THE    SPONTANEOUS   TUMOR 


"This  hypothesis  assigns  a  very  important  etiological  part  to  a 
constitutional  change  ensuing  with  advance  in  years.  The  ingenuity 
and  the  simphcity  of  the  conception  are  striking.  However,  sufficient 
account  has  not  been  taken  of  the  differences  existing  between  spon- 
taneous and  propagated  cancer,  as  consistently  emphasized  from  this 
laboratory,  since  the  hypothesis  was  based  upon  the  unfavourable 
results  of  removing  a  spontaneous  tumour  from  its  native  environment 
and  transplanting  it  into  normal  animals,  without  giving  due  considera- 
tion to  any  other  possible  factor  than  the  assumption  of  a  differential 
of  cell-avidities.  At  the  time  when  the  hypothesis  was  formulated,  the 
investigations  conducted  in  this  laboratory  had  already  fully  demon- 
strated that  the  hemorrhagic  mammary  tumours  could  be  transplanted 
with  ease,  whereas  Ehrlich  had  concluded  that  they  were  practically 
untransplantable  and  therefore  of  low  avidity.  The  transplantation 
of  spontaneous  tumours  had  been  shown  to  give  better  results  in  young 
than  in  old  animals,  and,  therefore,  the  peculiar  age-incidence  of  cancer 
was  bound  up  with  the  inception  and  not  with  the  continued  growth 
of  cancer.  The  fact  that  old  animals  did  not  yield  a  soil  uniformly 
more  suitable  for  growth  than  did  young  animals,  led  as  a  matter  of 
course  to  an  investigation  of  the  quality  of  the  soil  which  mice  suffer- 
ing naturally  from  cancer  offered  for  the  growth  of  their  own  and 
other  tumours,  and  to  the  investigation  of  the  most  important  question 
of  individuality.  ..."  A  glance  at  the  following  table  "...  will 
show  how  it  is  possible  to  contrive  experimental  tests  of  the  hypoth- 
esis, by  ascertaining  how  tumours  behave  in  animals  of  normal  avidity, 
and  in  animals  in  which  departures  from  it  are  assumed  to  have 
occurred  because  they  have  developed  cancer.     The  table,  embody- 


Mice  with  Spontaneous 
Cancer 

Normal  Mice 

Spontaneous  Tumour  A    .     . 
"       B    .     . 

A            B 

+ 

-           + 

—      0/3  s 
+     3/35 

"        C   .     . 
"        D  .     . 
"        E  .     . 

C        D        E 

+         - 

-  + 

-  -          + 

o/iooo 

+   4/26 

THE    SPONTANEOUS   TUMOR  213 

ing  some  of  Haaland's  experiments  with  five  mice  and  their  spon- 
taneous tumours,  summarizes  the  kind  of  results  obtained.  ...  In 
the  first  experiment,  tumour  A,  when  tested  in  normal  mice,  does 
not  grow,  therefore  the  avidity  of  mouse  A  is  below  normal.  Tumour 
B  grows  in  normal  mice,  therefore  it  must  have  a  greater  avidity  than 
tumour  A,  and  a  still  greater  avidity  than  the  body-cells  of  mouse  A ; 
but  tumour  B  will  not  grow  in  mouse  A.  It  follows  that  the  hypothesis 
is  inadequate  to  explain  the  failure  of  transplantation  in  this  case.  In 
the  second  experiment,  two  mice,  C  and  D,  have  been  picked  out  whose 
tumours  would  not  grow  when  tested  on  a  thousand  animals  of  normal 
avidity ;  it  follows  that  tumours  C  and  D  were  growing  in  mice  C  and 
D  in  spite  of  an  avidity  very  much  below  the  normal,  and  also  that 
mice  C  and  D  had  an  avidity  even  lower  in  the  scale.  Nevertheless, 
a  tumour  E,  which  had  so  high  an  avidity  that  it  grew  easily  in  mice 
of  normal  avidity,  was  not  able  to  grow  in  mice  C  and  D,  of  which  the 
avidity  has  been  proved  to  be  so  low.  This  is  a  reductio  ad  ahsurdum. 
It  follows  from  these,  and  from  many  similar  or  slightly  different  experi- 
ments, that  Ehrlich's  atreptic  hypothesis  is  inadequate  to  explain  the 
growth  of  cancer  either  when  transplanted  into  a  fresh  host,  or  when 
growing  in  the  animal  in  which  it  arose,  and  it  may  be  inferred  is 
equally  inadequate  to  explain  the  cause  and  nature  of  cancer.  Without 
denying  that  cancer-cells  may'  have  inter  se  a  different  avidity  for 
food-stuffs,  the  explanation  of  the  development,  nature,  and  preven- 
tion of  cancer  is  not  to  be  sought  along  the  lines  indicated  by  Ehrlich's 
atreptic  hypothesis." 

HISTOLOGY 

During  the  first  few  years  of  the  investigation  of  mouse  tumors 
it  was  customary  to  speak  of  ''Jensen's  tumor,"  or  of  "Borrel's  tumor," 
an  expedient  which  could  from  the  nature  of  the  case,  however,  be 
but  temporary.  As  the  number  of  cases  under  observation  grew 
larger  it  became  desirable,  and  even  necessary,  that  some  sort  of 
classification  be  attempted.  It  was  found  possible  to  make  one,  par- 
tially satisfactory  at  least,  and,  furthermore,  that  this  would  follow, 
although  somewhat  roughly,  those  suggested  for  tumors  in  man. 

MichaeKs  ^  was,  perhaps,  the  first  to  attempt  to  classify  the  spon- 

^  Med.  Klin.,  1905,  i,  204. 
Zeitschrift  f.  Krehsforsch. ,  1906,  iv,  3. 


214  THE    SPOXTAXEOUS    TUMOR 

taneous  tumors,  arranging  them  under  three  heads.  The  first  two 
were  the  simple  alveolar  carcinoma,  which  was  sometimes  tubular, 
and  the  adeno-carcinoma,  often  signalized  by  the  formation  of 
cysts  and  papills.  In  those  of  the  third  t\pe,  the  parenchjnna  was 
di\'ided  into  alveoli,  as  in  the  first  group,  but  within  each  alveolus  the 
cells  were  wreathed  about  lumina  in  single  layers,  conferring  somewhat 
the  appearance  of  a  sweat  gland  on  cross-section.  The  acini  were  not  in 
contact,  however,  but  separated  by  irregularly  arranged  alveoli.  This 
type,  unnamed  by  ]\Iichaehs,  corresponds  to  the  malignant  adenomata. 
Apolant^  suggested  the  following  comprehensive  classification  for 
the  mammary  tumors  of  the  mouse  :  — 
I.  Adenoma. 

(a)  Adenoma  simplex, 
(h)  Cyst-adenoma  simplex. 

(c)  Adenoma  cysticum  cedematosum  s.  haemorrhagicnm. 

(d)  Cyst-adenoma  papilliforme. 
II.  Carcinoma. 

(a)  Carcinoma  simplex  aheolare,  including  cysto-carcinoma  haemor- 

rhagicnm. 

(b)  Carcinoma  papillare.  including  Jissure-forming  carcinoma. 
The  poverty  of  the  normal  mammary  gland  as  concerned  a  well- 
developed  stroma,  made  it  understandable  that  connective  tissue 
neoplasms  had  not  so  far  been  discovered  in  it.  The  mammary  tumors 
of  the  mouse  were  epithehal  growths,  the  ground  tA'pe  of  which  was 
represented  by  the  adenoma  simplex.  By  the  term  ground  type 
Apolant  ^^dshed  not  only  to  convey  the  idea  that  the  adenoma  was  at 
once  the  most  simple  of  all  growths  and  the  one  most  closely  allied 
to  the  structure  of  normal  mamma,  but  further,  to  emphasize  its 
genetic  relation  to  other  epithehal  tumors,  for  in  spite  of  a  great  variety 
in  structure  he  had  seen  no  growth  that  could  not  be  traced  back  to 
the  simple  adenoma. 

The  adenoma  simplex  in  its  adult  condition  was  more  or  less 
lobular  in  microscopic  structure,  separated  by  a  capsule  from  the 
normal  gland  and.  as  a  rule,  but  poorly  provided  \yiih  stroma.  The 
round  or  oval  acini  corresponded  in  general  to  the  normal  acini  of 
the  mamma,  although  they  lay  more  closely  together  and  were  not 
^  Arb.  a.  d.  Konigl.  Inst.f.  E.xp.  Therap.,  1906,  Heft  i,  11. 


THE    SPONTANEOUS   TUMOR 


215 


arranged  in  groups  within  the  lobules.  The  cells,  arranged  in  one 
layer,  were  usually  small,  approximately  cubical  in  shape,  and  were 
furnished  with  a  relatively  large  nucleus  rich  in  chromatin.  Mitoses 
were  infrequent  and  never  of  pathological  type.  The  acini,  like  those 
of  the  normal  mamma,  usually  contained  a  coUoid-Hke  material 
staining  with  acid  dyes,  and  either  filhng  the  lumina  entirely  or 
irregularly  retracted  from  their  walls.  Altogether,  the  histological 
picture  imitated  very  closely  that  of  a  parenchymatous  goiter.  The 
blood  supply  was  usually  in  proportion  to  the  amount  of  stroma, 
although  some  areas  might  be  well  provided  with  vessels  while  others 
in  the  same  tumor  were  supplied  but  poorly.  In  very  young  tumors, 
below  the  size  of  a  lentil,  a  lobular  structure  was  not  usually  demon- 
strable, and  although  these  were  separated  to  some  extent  from  the 
normal  gland  by  strands  of  connective  tissue,  at  other  points  there 
was  such  a  gradual  transition  that  it  was  impossible  to  differentiate 
between  the  newly  formed  acini  and  the  mamma  itself.  The  dis- 
tinction was  rendered  more  difficult  since  neither  the  form  of  the  alveoli 
nor  that  of  its  cells  departed  very  far  from  the  normal  type.  As  these 
immature  growths  were  distinguished  from  the  true  adenomata  by 
the  possession  of  ducts  which  were  traceable  into  those  of  the  nor- 
mal gland,  they  might  with  more  justice  be  described  as  local  hy- 
pertrophies than  as  tumors  in  the  strict  sense  of  the  word.  Never- 
theless, a  sharp  distinction  between  the  two  was  impossible,  and  not 
infrequently  both  forms  were  present  at  one  and  the  same  time,  the 
hypertrophic  moiety  still  in  intimate  connection  with  the  mamma,  the 
adenomatous,  on  the  other  hand,  surrounded  by  a  connective  tissue 
capsule.  Occasionally  a  number  of  mitoses  greater  than  was  ever 
associated  with  true  adenoma  could  be  discovered  in  the  cells  of  local 
hypertrophic  areas,  and  in  such  cases  careful  examination  would 
nearly  always  disclose  regions  where  the  glandular  epitheHum,  having 
suddenly  taken  on  atypical  growth,  was  progressing  directly  toward 
carcinoma  without  the  intervention  of  an  adenomatous  stage. 

Secondary  alterations,  to  which  the  adenomata  always  suc- 
cumbed after  any  considerable  duration,  might  affect  either  the 
parenchyma  or  the  stroma.  As  an  outcome  of  the  former  there 
resulted  a  cyst-adenoma  simplex,  and  of  the  latter,  an  adenoma 
cysticum  cedematosum  s.  haemorrhagicum. 


2l6  THE    SPONTANEOUS   TUMOR 

The  change  in  the  parenchyma  resulting  in  the  evolution  of  a  cyst- 
adenoma  simplex  was  a  dilatation  of  the  acini  with  the  formation  of  re- 
tention cysts.  The  cubical  cells  lining  these  cavities  were  sometimes 
greatly  flattened  by  pressure  and  when  the  process  took  place  in  adja- 
cent alveoli  the  series  of  occasionally  intercommunicating  chambers 
thus  produced  recalled  vividly_  the  structure  of  lung  as  seen  under 
the  low  power. 

The  adenoma  cysticum  oedematosum  s.  haemorrhagicum  was  marked 
in  its  early  stages  through  the  separation  of  certain  still  normal  alveoli 
from  their  fellows  by  an  edematous  stroma,  or  later,  byfinal  destruction, 
of  the  isolated  alveoli  from  increase  of  the  edema.  The  edema  varied 
according  to  whether  stasis  in  the  tumor  involved  more  particularly  the 
blood  or  the  lymph  vessels.  In  the  former  case,  dilated  capillaries  trav- 
ersed the  growth,  often  conferring  the  appearance  of  a  cavernoma,, 
and  it  was  not  unusual  for  the  vessel- wall  to  rupture,  giving  rise  to  a 
more  or  less  extensive  hemorrhage.  Generally,  however,  the  lymph 
channels  were  primarily  or  concomitantly  affected,  and  an  edema  was 
produced  which  evolved  the  lesions  just  described,  before  stasis  in  the 
blood  vessels  became  apparent. 

The  fate  of  the  adenomata  was  thus  a  varied  one,  and  depended 
upon  whether  secondary  degenerations  ran  their  course  in  the  paren- 
chyma or  in  the  interstitial  tissues.  Although  the  lesions  just  dis- 
cussed could  exist  separately  to  a  certain  degree,  they  were  sa 
combined  in  their  later  stages  that  discrimination  was  impossible. 

The  essential  characteristic  of  the  cyst-adenoma  papilliferum  lay 
in  this,  that  in  contradistinction  to  the  types  previously  described^ 
cellular  proliferation,  keeping  pace  at  least  with  the  dilatation  of  the 
cysts,  or  more  usually  outstripping  it,  created  a  papillary  structure. 
This  rather  rare  tumor  owed  its  peculiar  architecture  to  the  energetic 
stroma  development.  As  the  cysts  dilated,  their  form  became  irregu- 
lar from  introversions  of  their  walls,  while  at  the  same  time  the  lining 
epithelium  threw  out  tiny  buds  which,  aided  by  the  growth  of  new 
connective  tissue,  gradually  developed  into  delicate  papillae.  In  the 
presence  of  very  vigorous  cell  growth  these  papillae  could  project  lateral 
branches,  although  Apolant  had  never  seen  any  very  intricate  pattern, 
produced  in  this  way. 

The    carcinoma    simplex    alveolare     originated    from     adenomata 


THE    SPONTANEOUS   TUMOR  217 

which  had  undergone  neither  cystic  nor  hemorrhagic  transformation, 
and  the  mahgnant  change  was  initiated  either  in  circumscribed  or 
more  extended  locahties.  There  occurred  in  the  midst  of  the  or- 
dinary adenomatous  tissue  one  or  more  sharply  defined  areas,  where 
the  epithehal  cells  formed  a  solid  nest  without  any  trace  of  a  lumen. 
Mitoses  were  seldom  lacking  even  in  this  earliest  stage,  and  their  pres- 
ence afforded  a  further  distinction  between  the  young  carcinoma  and 
the  surrounding  adenoma.  Serial  sections  demonstrated  such  entire 
isolation  of  areas  of  carcinomatous  transformation  from  one  another, 
that  their  origin  could  be  considered  multicentric.  The  mahgnant 
change  seldom  developed  without  the  occurrence  of  distinct  morpho- 
logical alterations,  such  as  a  gradual  increase  in  the  size  of  the  cells. 
These  elements  assumed  a  characteristic  vesicular  appearance,  while 
with  the  increment  of  protoplasm  there  was  associated  an  enlarge- 
ment of  the  nucleus.  Hyperchromatic  and  other  atypical  mitoses 
were  abundant  in  this  tumor  type  as  they  were  in  all  other  rapidly 
growing  mouse  carcinomata.  As  a  rule  the  growth  of  new  blood 
vessels  was  unable  to  keep  up  with  the  rapid  prohferation  of  the 
parenchyma,  whence  more  or  less  extensive  areas  of  degeneration 
occurred  in  the  central  portions  of  the  tumor  even  at  an  early 
stage  of  development.  Nevertheless,  there  were  alveolar  car- 
cinomata which  possessed  an  adequate  blood  supply,  and  these 
one  might  be  inclined  to  class  among  the  endotheliomata  on 
account  of  the  seemingly  close  relation  between  blood  vessels  and 
tumor  cells,  were  it  not  that  an  endothelial  origin  had  never  yet  been 
indubitably  demonstrated  for  any  mouse  tumor. 

Closely  connected  with  the  alveolar  variety,  and  a  derivative  of  it 
rather  than  a  separate  type,  was  the  cysto-carcinoma  haemorrhagicum. 
This  tumor  was,  in  fact,  an  alveolar  carcinoma  that  had  developed 
upon  a  cystic  or  hemorrhagic  adenoma,  and  a  typical  example  at  the 
height  of  development  had  the  appearance  of  a  transformed  adenoma, 
with  cystic  dilatation  oi  the  alveoli  and  extensive  hemorrhages  into 
the  interstitial  tissue.  An  adenomatous  structure  was  no  longer  to 
be  recognized  in  the  outlying  parts,  and  the  cystic  or  hemorrhagic 
portions  were  surrounded  by  cells  arranged  in  the  most  disorderly 
manner.  In  later  stages  the  columns  of  tumor  cells  isolated  by  blood 
spaces  gradually  succumbed  until  finally,  the  proliferative  power  of 


2l8  THE    SPONTANEOUS    TUMOR 

the  cells  exhausted,  the  whole  process  terminated  in  a  cyst  filled 
with  thick,  brown,  bloody  debris.  The  relatively  benign  nature  of 
this  variety  was  indicated  further  by  a  noteworthy  lack  of  mitoses, 
a  condition  which  was  in  sharp  contrast  to  the  great  number  seen  in 
true  alveolar  tumors. 

Carcinoma  papillare  was  a  much  less  common  growth  than 
alveolar  carcinoma.  While  in  the  latter  type  an  acinous  arrangement 
of  the  cells  with  lumen  formation  occurred  but  rarely,  in  that  now  un- 
der discussion  the  presence  of  lumina  was  a  constant  characteristic.  If 
the  lumina  retained  their  original  size  the  structure  of  the  tumor  corre- 
sponded very  closely  to  that  of  malignant  adenoma,  but  cystic  enlarge- 
ment produced  the  true  papillary  carcinoma.  So  long  as  the  growths 
contained  no  papillse  they  might  be  termed  fissure-forming  adeno-carci- 
nomata,  for  the  lumina,  instead  of  being  round  or  oval,  were  narrow  and 
protracted  or,  at  other  times,  tortuous  or  triangular.  The  epithelial 
cells  at  first  inclosed  these  openings  in  a  single  layer  but  evinced  their 
carcinomatous  character,  notwithstanding  this  arrangement,  by  mitos- 
ing  freely  and  furthermore,  by  joining  with  neighboring  groups  to  form 
an  extensive  reticulum.  Large  solid  cell  nests  were  not  often  encoun- 
tered because  of  the  frank  tendency  toward  lumen  formation,  and  the 
stroma  was  developed  to  a  slight  extent  only.  While  this  fissure- 
forming  variety  might  persist  in  pure  form,  transitions  between  it 
and  the  true  papillary  type  were  more  usual.  The  process  was  quite 
analogous  to  that  which  ran  its  course  in  the  papillary  cyst-adenomata. 
Coincidently  with  dilatation  of  the  acini  their  lining  epithelium  ex- 
truded processes  into  the  lumina,  and  these  gradually  developed 
into  long  branched  papillae.  The  papillary  adeno-carcinomata,  be- 
sides being  evolved  from  tumors  of  the  fissure-forming  type  as  just 
described,  occasionally  originated  in  simple  adenomata  through  a 
sudden  widening  of  the  lumina  followed  by  a  vigorous  ingrowth  on 
the  part  of  the  epithelium. 

Although  the  several  varieties  above  described  were  the  most  charac- 
teristic forms  of  mouse  carcinoma,  Apolant  pointed  out  that  the 
account  as  given  was  by  no  means  complete,  for  malignant  tumors 
of  uniform  structure  were  very  rare,  and  the  multitude  of  types 
was  so  enriched  by  manifold  combinations  that  an  accurate  descrip- 
tion of    them  all  was  hardly  possible. 


THE    SPONTANEOUS    TUMOR  219 

According  to  Murray/  the  histological  variations  presented  by 
mammary  carcinomata  could  be  referred  with  but  few  exceptions  and 
by  easy  gradations  to  an  acinous  ground  type  which,  in  ks  turn,  led 
directly  to  the  structure  of  the  normal  mammary  gland ;  furthermore, 
the  parenchyma  of  any  single  tumor  might  exhibit  several  of  these 
modilications  simultaneously  or  successively.  Although  purely  acinous 
growths  were  extremely  rare,  spontaneous  tumors  without  any  trace 
of  an  adenomatous  arrangement  were  seldom  met  with.  Apolant 
had  inferred,  from  the  association  of  the  adenomatous  "v\dth  other 
structural  t}'pes,  that  alveolar  carcinomata  and  adeno-carcinomata 
arose  directly  from  preexisting  adenomatous  portions,  but  Murray 
was  of  the  conviction  that  the  course  of  transformation  was  usually 
in  the  opposite  direction,  that  is,  that  an  area  originally  alveolar 
became  spht  up  into  acini  by  penetrating  connective  tissue  and 
capillaries.  Still,  the  converse  process,  by  which  the  acinous  was 
transformed  into  the  alveolar  structure,  was  frequently  seen,  but 
its  interpretation  in  the  primary  tumor  was  more  difficult. 

Edematous  and  hemorrhagic  changes  in  the  stroma  were  more 
apt  to  occur  in  those  tumors  where  an  extremely  delicate  connective 
tissue  was  associated  with  thin-walled  blood  vessels.  Fluid  exudate 
accumulated  between  the  walls  of  the  capillaries  and  the  adjacent 
stroma,  so  that  the  vessels  appeared  to  be  suspended  in  wide  spaces 
filled  with  a  light  flocculent  coagulum.  With  this  condition  there 
was  generally  associated  a  dilatation  of  the  capillaries,  pointing  to  a 
partial  stasis  of  the  circulation  as  the  primary  change.  Hemorrhage 
into  the  widened  lymph  spaces  surrounding  the  vessels  frequently 
occurred,  and  when  the  acini  of  the  parenchyma  had  been  dilated  into 
cysts  such  blood  extravasations  easily  passed  through  their  attenuated 
walls  and  distended  the  ca\'ities.  The  thin  trabeculae  of  parench}Tna 
intervening  between  adjacent  cysts  were  often  much  compressed 
when  the  dilatation  was  extreme,  and  the  vascular  endothehum  might 
be  destroyed  for  long .  distances  —  a  condition  which,  particularly 
in  old  growths,  produced  the  appearances  that  had  led  v.  Hanse- 
mann  and  others  to  place  many  of  the  mouse  tumors  among  the 
endotheliomata. 

1  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  69. 


220  THE    SPOXTAXEOUS    TUMOR 

Apolant's  classification  was  fully  indorsed  by  Gierke  ^  who,  however, 
emphasized  the  fact  that  it  was  purely  histological  and  that  it  dealt  \\ith 
tumors  biologically  identical  and  varying  only  slightly  in  their  micro- 
scopic appearance.  As  regarded  the  conversion  of  adenomatous  into 
carcinomatous  structure,  Gierke  was  of  the  opinion  that  Apolant  had 
been  in  error,  and  that  exactly  the  reverse  evolution  took  place,  the 
acinous  portions  arising  from  the  alveolar.  This  would  correspond  to  a 
difl'erentiation  (maturation)  of  the  tissue  of  the  tumor,  and  was  com- 
parable with  the  formation  of  Pfliiger's  primordial  "egg  tubes'"  in  the 
ovary,  or  with  the  development  of  the  embr\"onic  or  strumous  foUicles 
of  the  thyroid  gland.  As  Apolant  had  stated.  A'ariations  in  the  rate 
of  growth  determined,  to  a  certain  degree,  variations  in  architecture, 
and  this  observation  made  it  easier  to  understand  the  significance  of 
histological  structure.  The  epithehal  cells  would  differentiate  faultily 
when  gro^A■ing  at  a  rapid  pace  and  would,  in  consequence,  assume  a 
garb  histologically  more  malignant  than  that  which  they  possessed 
when  growth  was  slower.  And  yet.  such  relations  between  structure 
and  growth  rate  did  not  always  obtain,  and  there  was  a  whole  series 
of  other  factors  involved,  including  the  behavior  of  the  connective 
tissue  and  the  general  constitution  of  the  animal  itseh. 

CLINICAL   COURSE 

A  priman,'  growth  of  the  mouse  pursues  much  the  same  course  as  does 
a  neoplasm  in  the  human  subject.  Spontaneous  absorption  may  take 
place  and  has,  in  fact,  been  recorded  by  EhrHch^  as  an  occurrence  not 
particularly  rare.  ]\Iurray.'^  on  the  other  hand,  thought  that  while 
absorption  was  not  uncommon  as  a  localized  process  affecting  small 
areas,  the  disappearance  of  an  entire  tumor  was  a  very  unusual  event, 
and  although  he  had  frequently  observed  temporary  arrest  of  growth 
and  in  some  cases  even  an  actual  diminution  in  size,  the  usual  course 
was  a  progressive  increase  in  the  dimensions  of  the  nodule.  The  rate 
at  which  growth  took  place  was  variable,  the  most  rapid  occurring 

^  Beitr.  zur  path.  Anat.,  etc..  I'Ziegler),  1908,  xliii,  336. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  124. 
^  Arb.  a.  d.  Konigl.  Inst.f.  Exp.  Therap.,  1906.  Heft  i.  82. 

^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  loi. 


THE    SPONTANEOUS    TUMOR  221 

among  the  hemorrhagic  carcinomata  in  which  sudden  increments 
(although  sometimes  due  to  an  extravasation  of  blood)  not  infrequently 
super\'ened  as  the  result  of  an  almost  explosive  proHferation  of  the 
parenchyma. 

Haaland  ^  recorded  a  few  mice  which  had  been  able  to  rid  themselves 
of  sporadic  growths.  In  one  of  these  animals,  although  the  absorp- 
tion of  a  spontaneous  tumor  was  under  way,  another  was  growing 
progressively  at  the  same  time  and  producing  large  metastases  in 
the  lungs  and  liver.  In  this  case,  therefore,  the  disappearance  of  a 
sporadic  neoplasm  was  due  to  local  conditions  affecting  the  tumor  cells 
themselves  rather  than  to  the  intervention  of  general  constitutional 
changes. 

Examined  under  the  microscope,  disappearing  nodules  were  found 
to  contain  a  fair  amount  of  healthy  tumor  tissue  showing  no  signs  of 
active  proKferation  and  surrounded  by  a  very  sclerotic  connective 
tissue.  At  the  periphery,  and  scattered  through  the  growth,  were 
numbers  of  large  phagocytes,  some  of  which  were  filled  with  brownish 
granules  while  others  possessed  a  vacuolated  protoplasm  Hke  that  of 
the  phagocytes  seen  in  spontaneously  regressing  propagable  tumors. 
These  cells  appeared  not  only  as  a  reaction  zone  outside  the  alveoli, 
but  also  within  them,  replacing  by  degrees  the  parenchymal  cells. 
The  resemblance  of  the  picture  to  that  accompanying  the  absorption 
of  transplantable  tumors  lay  chiefly  in  the  presence  of  phagocytes 
and  sclerotic  connective  tissue,  whereas  the  infiltration  of  small 
round  cells  usually  encountered  in  propagable  tumors  undergoing 
absorption  was  less  marked. 

Discussing  the  effect  of  a  spontaneous  growth  upon  the  animal 
bearing  it,  Murray  ^  said  that  the  weight  of  the  mouse  generally  in- 
creased slowly  with  the  growth  of  the  tumor  until  ulceration  or 
hemorrhage  supervened.  A  diminution  in  weight  then  set  in,  and  was 
always  a  symptom  of  the  gravest  import,  for  seldom  did  an  animal 
survive  more  than  two  weeks  after  its  inception. 

The  result  of  operative  removal  of  sporadic  growths  was  discussed 
by  Murray  as  follows  :  — ■ 

"When  a  large  tumour  is  removed  by  operation  from  a  mouse,  the 

'  Fourlh  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  191 1,  51. 
^  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  103. 


222  THE    SPOXTANEOUS    TUMOR 

animal  loses  weight  in  excess  of  that  represented  by  the  tumour  and 
blood  loss.  This  is  gradually  regained  in  the  succeeding  week  or  two 
weeks,  and  then  the  weight  remains  constant.  Minor  variations  of 
a  half  to  one  gram  unless  progressive  from  week  to  week  are  of  no 
importance.  Inter-current  illnesses  are  always  accompanied  by  loss 
of  weight,  sometimes  considerable.  Should  recurrence  take  place, 
the  animal  at  first  increases  in  weight,  as  already  noted.  Loss  in 
weight  generally  indicates  an  approaching  lethal  issue,  either  from  too 
great  nutritive  demands  by  the  recurrent  tumour,  or  from  respiratory 
embarrassment  due  to  extensive  pulmonary  metastases.  The  fre- 
quency with  w^hich  recurrence  supervenes  after  apparently  complete 
extirpation,  is  surprising  when  the  encapsulated  appearance  of  these 
tumours  to  the  naked  eye  is  borne  in  mind.  Early  operation,  as  in 
man,  gives  the  best  promise  of  lasting  freedom  from  recurrence.  Out 
of  48  animals  operated  on  .  .  .  recurrence  took  place  in  23,  two 
recurring  three  times,  six  twice,  and  the  remainder  once.  The  interval 
of  sur\dval  between  the  first  operation  and  death  averaged  three  to 
six  weeks  in  the  later  operations,  and  in  five  cases  was  more  than  100 
days.  .  .  .  The  number  of  recurrences  and  the  length  of  survival 
are  not  strictly  comparable  with  similar  data  from  the  human  subject, 
since  the  prolongation  of  Hfe  is  of  prime  importance  in  man,  but  in 
the  case  of  the  mouse  other  considerations  than  the  prolongation  of 
Hfe  have  such  importance  that  the  animal  may  have  to  be  sacrificed 
before   death  would  have   occurred." 

Murray's  cHnical  investigations  were  continued  by  Haaland  ^  on 
a  material  consisting  of  three  hundred  and  fifty-three  primary  growths, 
occurring  in  two  hundred  and  eighty-eight  mice.  Roughly  speaking, 
90%  of  the  tumors  were  adeno-carcinomata  of  the  mamma  corre- 
sponding very  closely  in  their  histology  to  the  descriptions  of 
Apolant  and  ^Murray. 

]\Iost  of  the  ablations  were  performed  as  early  and  as  completely 
as  possible,  but  the  difficulty  of  total  removal  was  increased  by  the 
wide  distribution  of  the  mammary  apparatus  and  the  relatively  large 
size  of  the  tumors.  Among  one  hundred  and  sevent)^-four  operated 
mice  ninety-six  exhibited  recurrence  which,  in  two-thirds  of  the  cases, 
took  place  before  the  end  of  the  sixth  week,  and  in  one-fourth  more 

^Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  igii,  49. 


THE    SPONTANEOUS    TUMOR  223 

between  the  sixth  and  tenth  weeks.     Only  isolated  instances  occurred 
later  than  this. 


RELATION   BETWEEN   TUMOR  AND   HOST 

The  relation  between  a  spontaneous  tumor  and  the  animal  bearing 
it  was  one  of  the  first  problems  to  receive  attention. 

Loeb  ^  found  that  an  adenoma  of  the  mammary  gland  in  a  white 
rat  would  grow  in  the  rat  herself  but  not  in  other  rats,  and  Loeb 
and  Leopold-  extended  this  experiment  to  include  the  transplan- 
tation of  one  of  the  common  mixed  mammary  tumors  of  the  dog, 
which  they  had  discovered  in  a  spaniel.  Grafts  were  inoculated  into 
three  other  dogs  (two  spaniels  and  a  fox  terrier),  but  did  not  grow, 
while  all  of  the  pieces  implanted  into  the  original  animal  remained 
alive,  neither  increasing  nor  decreasing  in  size. 

Bashford "  succeeded  in  implanting  two  mice  with  their  own  spon- 
taneous tumors,  even  though  inoculations  into  normal  animals  were 
in  vain.  In  a  third  experiment  the  grafting  of  a  growth  into  the 
animal  herself  was  fruitless,  but  fragments  grew  in  two  out  of  one 
hundred  and  fifty-six  healthy  mice  as  well  as  in  one  of  the  two 
referred  to  above  as  having  given  a  positive  result  upon  inoculation 
with  their  own  tumors. 

Bashford,  Murray,  arid  Cramer  ^  concluded  tentatively  in  the  fol- 
lowing year,  however,  that  mice  in  which  tumors  had  originated  were 
not  much  more  susceptible  to  other  grafts  than  normal  animals,  and 
that  the  subject  of  a  primary  tumor  could  be  inoculated  only  excep- 
tionally with  its  own  neoplasm.  This  latter  conclusion,  as  will  be 
seen  on  a  succeeding  page,  does  not  agree  with  the  results  of  more 
extended  investigation  by  Bashford  and  his  colleagues. 

Borrel  and  Petit  ^  inoculated  a  cancer  of  the  horse  into  the  animal 
in  which  the  growth  had  arisen,  and  into  a  normal  horse.  Of  four 
auto-inoculated  grafts  two  were  successful,  although  all  transplan- 
tations failed  in  the  normal  animal. 

^  Jour.  Med.  Research,  1902,  N.S.,  iii,  46. 

2  Jour.  Med.  Research,  1907-1908,  N.S.,  xii,  299.      ^  Briti.'ih  Med.  Jour.,  1906,  ii,  208. 

*  Proc.  Roy.  Soc,  Series  B,  1907,  Ixxix,  170. 

Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  323. 
^  Bull,  de  rinst.  Past.,  1907,  v,  1033. 


2  24  THE    SPONTANEOUS    TUMOR 

Apolant  ^  ingrafted  eight  mice  each  with  its  own  spontaneous 
tumor  and  succeeded  in  obtaining  growth  in  six  of  them.  Eighty 
normal  controls,  on  the  other  hand,  afforded  only  three  daughter 
tumors,  all  of  them  from  the  same  sporadic  growth.  Of  two  inocula- 
tions into  other  spontaneously  affected  mice,  one  was  fruitful  and  one 
was  not,  and  the  tumor  successfully  transplanted  had  been  inoculated 
with  a  negative  outcome  into  the  animal  in  which  it  arose.  This 
seemed  to  Apolant  to  speak  for  a  considerable  predisposition  on  the 
part  of  spontaneously  affected  animals  toward  the  implantation  of  other 
tumors,  the  more  so  because  such  mice  were  always  old,  and  in  old  ani- 
mals the  outcome  of  inoculation  was  usually  much  lower  than  in  young. 

Ribbert  ^  inoculated  several  fragments  of  a  fibroma  into  a  dog  from 
which  it  had  just  been  removed,  and  at  the  end  of  four  months  found 
that  each  had  attained  the  size  of  a  walnut.  Transplantation  of  grafts 
from  these  secondary  tumors  into  the  dog  itself  was  again  successful, 
but  further  attempts  carried  out  in  another  dog  were  without  result. 

The  question  of  the  relative  suitability  of  an  animal  for  the  im- 
plantation of  its  own  tumor  was  very  fully  investigated  by  Haaland.^ 

"Out  of  59  epithelial  tumours  of  varied  histology,  57  have  grown 
on  transplantation  of  the  cells  into  the  same  spontaneously  affected 
animal.  Only  two  cases  have  been  negative ;  of  these,  one  should 
not  be  counted,  for  the  mouse  was  ill  practically  the  whole  time  it 
was  under  observation,  and  died  four  weeks  after  the  inoculation.  The 
other  negative  case  occurred  in  a  mouse  surviving  for  26  weeks  after 
inoculation  without  exhibiting  any  growth  at  the  point  of  inoculation. 
Of  non-epithehal  tumours  there  are  4,  three  spindle-cell  sarcomata 
positive  on  re-inoculation,  the  fourth  a  melanotic  tumour  of  peculiar 
structure  and  of  very  low  power  of  growth ;  no  evident  increase  was 
noted  of  the  grafts  re-inoculated  simultaneously  in  four  different 
places  into  the  mouse  in  which  it  had  arisen,  although  the  tumour 
cells  remained  alive  for  four  months. 

"In  the  cases  where  the  grafting  has  been  carried  out  subcutane- 
ously,  the  period  elapsing  between  implantation  and  the  appearance  of 
a  palpable  nodule  showing  increase  in  size  is  as  follows  :  — 

^  Zeitsckrift  f.  allg.  Physiol.,  1909,  ix,  Sammelreferat,  80. 

'  Centralbl.  f.  allg.  Path.,  etc.,  1910,  xxi,  625. 

3  Lancet,  1909,  ii,  1588.     Fourth  Sci.  Report,  Imperial  Cancer  Research  Fund,  London, 

1911,  57- 


THE    SPONTANEOUS    TUMOR  225 

End  of  I  St  week  6 
2d     "      23 

''       4th    "      8   (in   two  of  these  cases  the  inoculated  tumour 
remained  stationary  for  a  long  time  —  in  one  case  for  eleven 
weeks  —  then   grew   slowly) 
End  of  5  th  week  3 

"      6th     "      I  (large  dose) 

"  7th  "  I  (  "  "•  ) 
"On  the  whole  the  rapidity  of  growth  of  the  graft  corresponds  to 
the  rate  of  growth  of  the  primary  tumour,  and  the  same  individual 
characteristics  are  retained  in  the  histological  picture.  Two  different 
tumours  of  the  same  mouse  may  exhibit  different  powers  of  growth 
when  re-transplanted  into  the  mouse  itself.  Sometimes,  however, 
it  is  surprising  how  rapidly  a  graft  from  an  apparently  stationary 
haemorrhagic  tumour  may  grow.  In  the  great  majority  of  cases  the 
graft  is  already  developing  into  a  new  tumour  2-3  weeks  after  inocula- 
tion into  the  same  spontaneously  affected  mouse.  This  is  on  the  whole 
considerably  sooner  than  spontaneous  tumours  develop  when  first 
transplanted  into  normal  mice,  and  the  subsequent  rate  of  growth 
is  much  more  rapid  than  that  observed  in  normal  animals.  This 
result  is  most  easily  accounted  for  by  a  large  number  of  cells  surviving 
transplantation,  and  the  circumstance  of  their  being  more  in  concord 
with  their  surroundings." 

The  general  result  of  Haaland's  experiments  was  thus  that  auto- 
plastic inoculation  of  a  spontaneously  attacked  mouse  was  nearly 
always  fruitful,  except  in  the  case  of  tumors  of  very  low  growth  power. 
Cells  re-introduced  into  the  organism  to  which  they  were  native 
found  all  the  necessary  conditions  for  continued  existence  and  growth, 
but  ingrafted  into  other  spontaneously  affected  mice  or  into  normal 
ones,  were  in  a  less  favorable  situation,  and  inoculation  was  accordingly 
not  so  often  successful.  This  difference  between  the  animal  in  which 
the  tumor  originated  and  any  other  animal  has  been  well  expressed 
by  Bashford,  Murray,  and  Cramer  :  ^  — 

''The  influence  of  the  individuahty,  i.e.  the  sum  total  of  changes 

1  Proc.  Roy.  Soc,  Series  B,  1907,  Ixxix,  184. 

■  Third  Sci.  Report,  Imperial  Cancer  Research  Fund,  London,  1908,  337. 


226  THE    SPONTANEOUS    TUMOE. 

due  to  the  past  life  of  the  organism,  will  be  to  make  any  mouse  dif- 
ferent from  all  others,  and  these  differences  will  increase  the  longer 
the  animal  Hves.  The  difficulty  of  obtaining  success  in  the  primary 
transplantation  of  spontaneous  tumours  would  be  accounted  for  by 
supposing  that  the  new  animals  provide  an  environment  to  the  cancer 
cells  so  strange,  that  they  cannot  survive  the  interruption  to  their 
nutrition.  Their  failure  to  grow  does  not  necessarily  imply  that  they 
would  fail  to  proHferate  in  their  new  hosts  if  the  conditions  to  which 
they  had  been  accustomed  could  be  immediately  suppHed  in  the  experi- 
ment. Cells  which  have  lived  and  become  accustomed  to  the  body 
fluids  of  one  mouse  for,  say,  two  years,  may  easily  die  or  fail  to  adapt 
themselves  when  transferred  to  the  bodies  of  new  animals.  The 
frequency,  in  our  experience,  of  large  metastases  in  animals  sponta- 
neously affected  is  in  marked  contrast  to  the  difficulties  in  obtaining 
growth  in  normal  animals,  and  harmonises  well  with  this  view." 

As  Haaland  did  not  neglect  to  indicate,  his  experiments  suggested 
not  only  the  advantages  to  be  gained  by  the  surgeon  in  employing 
tissues  from  the  same  individual  in  all  transplantations  but,  further- 
more, the  peril  to  that  patient  in  whom  cancer  cells  were  disseminated 
throughout  an  operation  wound.  On  the  other  hand,  they  demon- 
strated the  relatively  insignificant  danger  to  be  apprehended  from 
cancer  cells  introduced  into  individuals  other  than  the  one  in  which 
they  had  taken  on  malignant  growth. 


CHAPTER   VIII 

TUMORS   OF   A   NATURE    STILL    UNDECIDED 

A  REVIEW  of  the  three  following  growths  has  been  relegated  to  a 
separate  chapter  because,  as  the  best  pathological  judgment  of  the 
day  is  still  divided  over  the  question  of  their  character,  it  seemed 
inexpedient  to  combine  the  results  following  their  investigation  with 
those  that  have  been  gained  through  the  examination  of  tumors  which 
have  been  almost  universally  accepted  as  mahgnant. 

TRANSMISSIBLE    LYMPHO-SARCOMA    OF    THE    DOG 

The  transmissible  "lympho- sarcoma"'  of  the  dog  is,  briefly,  a  tumor 
which  occurs  on  the  genital  organs  of  this  animal  as  the  result  of 
infection  during  coitus.  Histologically  it  is  indistinguishable  from 
a  small  round  cell  sarcoma,  while  in  its  clinical  course  it  reproduces 
many  characteristics  of  the  true  tumors ;  the  different  opinions  held 
by  various  authorities  concern  chiefly  the  manner  in  which  the  growth 
develops  after  having  been  introduced  into  a  new  host. 

The  first  investigator  to  examine  the  nature  of  this  tumor  appears 
to  have  been  Novinsky,^  who  reported  its  inoculation  and  the  conse- 
quent production  of  nodules  identical  in  structure  with  the  primary 
growth,  which  was  described  as  a  myxo-sarcoma.  Metastatic  deposits 
were  not  found. 

Wehr  ^  considered  the  growth  a  carcinoma.  He  observed  the 
spontaneous  absorption  of  transmitted  tumors,  and  in  one  instance 
the  presence  of  metastases  in  the  retroperitoneal  and  cervical  lymph 
nodes,  and  the  spleen. 

Duplay    and    Cazin  ^'endeavored    for    several    years    to    transmit 

1  Med.  Vestnik,  St.  Petersburg,  1876,  xvi,  289.  Cited  by  Sticker,  Arch.  f.  klin.  Chir., 
(v.  Langenbeck),  1906,  Ixxviii,  774. 

2  Verhandl.  d.  deiitschen  Gesellsch.f.  Chir.,  1889,  xviii,  Teil  ii,  86. 
Arch.  f.  klin.  Chir.,  (v.  Langenbeck),  1889,  xxxix,  226. 

^  Alii  dcir  xi  Congr.  med.  inlernaz.,  Rome,  1894,  ii,  Pat.  gen.,  etc.,  103. 

227 


2  28  TUMORS    OF   A   NATURE    STILL   UNDECIDED 

various  neoplasms  from  one  dog  to  another,  but  sixty  animals 
all  proved  refractory.  Positive  results  were  obtained,  however 
with  the  growth  now  under  discussion,  which  the  authors  described 
as  resembhng  very  closely  the  granulomata.  A  possible  metastasis 
was  noted  in  one  case. 

Geissler  ^  recorded  the  presence  of  nodules  throughout  the  body 
in  a  dog  bearing  a  transmitted  tumor,  but  whether  or  not  they  were 
genuine  metastases  it  was  impossible  to  say,  because  preservation  had 
miscarried.  The  tumor  was  not  the  typical  epithehal  carcinoma 
found  in  man. 

In  the  subsequent  discussion  of  this  paper  v.  Hansemann  expressed 
his  con\dction  that  the  tumor  was  not  a  carcinoma,  although  he 
would  not  deny  either  that  it  was  mahgnant  or  transmissible. 

Smith  and  Washbourn  -  described  in  detail  the  cHnical  course  of 
the  tumor  as  it  occurred  sporadically  in  dogs,  and  furnished  numerous 
instances  of  its  natural  transmission.  So  far  as  structure  was  con- 
cerned the  growths  were  sarcomata.  In  two  autopsies  carried  out 
upon  sporadically  affected  dogs  no  secondary  deposits  were  found 
in  the  viscera,  although  metastasis  had  taken  place  in  the  inguinal 
lymph  nodes.  In  no  case  where  the  disease  was  sporadic  did  regres- 
sion of  the  tumor  occur.  In  a  later  article  the  authors  ^  gave  an  ac- 
count of  successful  inoculation  in  thirteen  out  of  seventeen  dogs ;  and 
while  most  of  these  were  young,  one  old  animal  at  least  had  not  proved 
refractory  to  the  growth.  A  few  dogs  appeared  to  be  naturally  immune 
and  resisted  several  successive  attempts  at  transference,  while  animals 
which  had  been  able  to  rid  themselves  of  their  growths  were  invariably 
refractory  to  subsequent  inoculation. 

A  large  part  of  the  investigation  of  the  dog  tumor  has  been  prose- 
cuted by  Sticker,^  who  has  consistently  held  that  the  growth  was  a 

1  Vcrhandl.  d.  dcutschen  GcseUsch.  f.  Chir.,  1895,  xxiv,  Teil  i,  87. 
^  Trans.  Path.  Soc.  London,  1897,  xlviii,  310. 

Jour.  Path,  and  Bad.,  1898,  v,  99. 
^  British  Med.  Jour.,  1898,  ii,  1807. 
*  Zeitschrift  f.  Krebsforsch.,  1903-1904,  i,  413. 

Zeitschrift  f.  Krebsforsch.,  1906,  iv,  227. 

Arch.  f.  klin.  Chir.,  (v.  Langenbeck),  1906,  Ixxviii,  773 

Berl.  klin.  Woch.,  1907,  xliv,  486. 

Dent.  med.  Woch.,  1907,  xxxiii,  867. 


TUMORS    OF   A   NATURE    STILL   UNDECIDED  229 

round  cell  sarcoma ;  for  in  addition  to  its  microscopic  structure,  the 
recurrence,  the  infiltrative  growth,  the  formation  of  metastases  in 
the  regional  lymph  nodes,  and  the  fact  that  the  cells  were  able  to 
attain  the  general  circulation  were  all  evidences  of  its  sarcomatous 
nature. 

The  cells  differed  from  the  normal  lymphocytes  of  the  dog  by  their 
larger  size,  by  the  possession  of  a  distinct  nucleolus,  and  by  their 
staining  reactions.  At  an  early  stage  of  growth  the  elements  of  the 
tumor  lay  tightly  compressed  and  there  was  almost  no  intercellular 
tissue  to  be  found,  although  at  a  later  period  a  delicate  reticular 
connective  tissue  made  its  appearance.  In  older  portions  of  the 
nodules  dilated  capillaries  were  present,  and  the  rupture  of  their 
walls  produced  occasional  areas  of  hemorrhage. 

Cells  exposed  to  a  temperature  of  —  14°  C.  for  twenty-four  hours,  or 
heated  at  50°  C.  for  two  hours,  were  still  capable  of  proliferation,  but 
the  power  to^row  was  abolished  in  those  which  had  been  kept  at  —  11° 
C.  for  twenty-five_days.  The  fact  that  no  tumors  resulted  from  the 
introduction  of  crushed  cells,  or  of  filtered  or  centrifuged  emulsions, 
excluded  in  all  probability  an  extracellular  parasite  as  an  etiological 
factor,  and  it  had  been  found  impossible  to  demonstrate  an  organism 
by  means  of  the  usual  bacteriological  methods. 

Very  few  dogs  were  possessed  of  a  natural  immunity  and  implan- 
tation could  be  performed  in  practically  any  part  of  the  body,  while 
in  two  out  of  three  foxes  tested,  transmission  was  accomplished. 
Grafts  in  dogs  produced  no  inflammatory  reaction  in  their  neighbor- 
hood, and  the  new  tumor  was  not  formed  through  participation  of  the 
surrounding  connective  tissue.  Metastasis  took  place  by  way  of  the 
blood  or  lymph  streams,  but  not  very  frequently  in  either  case. 
Examination  of  the  blood  of  tumor-bearing  dogs  showed  an  increase 
in  the  number  of  polymorphonuclear  leucocytes  and  a  decrease  in 
that  of  the  lymphocytes  and  eosinophile  leucocytes,  while  in  the 
presence  of  dead,  tumor  material  large  mononuclear  lymphocytes 
(macrophages)  could  be  demonstrated.  Spontaneous  healing  occurred 
in  about  16  %  of  all  dogs  with  transmitted  tumors,  and  in  some  cases 
the  rate  of  diminution  was  very  striking  — -  as  in  one  where  a  tumor 
one  hundred  and  seven  days  old,  and  as  large  as  a  hen's  egg,  van- 
ished within  fourteen  days. 


230  TUMORS    OF   A   NATUIIE    STILL   UNDECIDED 

Dogs  in  which  tumors  were  regressing  or  had  entirely  disappeared 
were  always  immune  to  re-inoculation,  and  the  blood  of  these  resist- 
ant animals  had  in  two  cases  brought  about  a  cessation  of  growth 
and  partial  regression  in  two  subcutaneous  trnnors,  although  in  common 
with  the  serum  of  normal  dogs  it  had  no  effect  upon  tumor  cehs  in 
vitro. 

Animals  bearing  progressively  growing  tumors  were  re-inoculable, 
but  not  during  the  period  immediately  following  the  establishment 
of  the  first  tumor.  The  tissues  surrounding  a  growth  constituted  a 
tumor  zone,  and  the  rest  of  the  body  an  immune  zone  within  which 
the  development  of  a  second  graft  was  inhibited.  This  condition 
existed,  however,  for  a  certain  period  of  time  only,  and  as  the  tumor 
increased  in  size  it  extended  its  sphere  of  influence  at  the  expense 
of  the  immune  zone,  which  grew  progressively  smaller  until  finally 
the  organism  produced  no  more  immunizing  material.  A  second 
phase  then  commenced,  during  which  there  supervened  the  widespread 
occurrence  of  metastases.  These  periods  Sticker  called  the  pre- 
metastatic  and  the  metastatic  stages,  respectively. 

White  ^  thought  that  although  these  growths  had  been  frequently 
referred  to  as  sarcomata,  they  differed  from  that  type  of  neoplasm 
in  the  human  subject.  In  the  first  place,  they  were  highly  contagious, 
while  secondly,  they  never  infiltrated  the  surrounding  tissues,  gave 
rise  but  rarely  to  metastases,  and  were  very  slow  in  their  growth. 
They  had,  furthermore,  certain  analogies  with  the  infectious  diseases, 
such  as  the  high  degree  of  contagiousness  and  the  long  incubation 
period.  Still,  the  author  did  not  beheve  that  the  contagiousness  of 
these^rowths  could  safely  be  used  in  support  of  the  argument  for  the 
paj;asiticjiature  of  malignantjlisease,  since  the  infective  agent  niight 
be  the  tumor^ell^itself .  The  fact  that  the  tumors  could  not  be  trans- 
ferred to  any  animal  except  the  dog  pointed  to  the  conclusion  that 
transmission  was  an  example  of  implantation  rather  than  of  infection. 
White  had  been  informed  that  the  disease  was  occasionally  inherited. 

Bashford,  Murray,  and  Cramer  -  believed  that  in  spite  of  the  his- 
tological  similarity  between   this    tumor  and    the    sarcomata   there 

'^British  Med.  Jour.,  1902,  ii,  176. 

2  Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  No.  2,  Part  ii,  2)Z- 
Berl.  klin.  Wach.,  1905,  xlii,  1434. 


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TUMORS    OF   A   NATURE    STILL   UNDECIDED  23 1 

were  several  facts  which  mihtated  against  its  inclusion  under  that 
class  of  growth.  In  the  examination  of  a  case  of  natural  infection 
it  was  found  that  where  the  tumor  adjoined  the  areolar  tissue  of  the 
host  there  was  apparent,  unless  growth  had  been  so  rapid  as  to  pro- 
duce marked  pressure,  a  gradual  alteration  of  the  surrounding  connec- 
tive tissue  corpuscles.  While  these  cells  were  normally  elongated 
and  flattened  structures  with  densely  staining  nuclei,  a  gradual 
transition  occurred  between  this  type  and  that  characteristic  for  the 
parenchyma  of  the  fully  developed  tumor.  In  the  course  of  this 
transformation  the  cytoplasm  of  the  connective  tissue  cells  became 
more  voluminous  and  the  nuclei  of  these  elements  increased  in  size, 
but  stained  more  faintly.  Although  additions  to  the  tumor  mass  oc- 
curred by  this  conversion,  the  increase  in  size  of  the  growth  was  mainly 
due  to  the  active  division  of  cells  which  already  possessed  the  distinc- 
tive characteristics  of  tumor  elements;  hence  in  its  later  stages  the 
tumor  grew  almost  entirely  from  its  own  resources,  closely  imitating 
in  this  respect  a  true  malignant  new  growth. 

When  grafts  were  examined  after  removal  at  varying  intervals 
following  implantation,  it  could  be  seen  that  the  establishment  of  a 
new  tumor  was  accomplished  by  a  transformation  of  the  connective 
tissue  cells  at  the  inoculation  site  into  elements  indistinguishable 
from  those  of  the  primary  growth.  The  introduced  tumor  cells, 
however,  degenerated  very  rapidly,  only  a  few  retaining  their  vitality 
for  three  or  four  days. 

Another  reason  against  including  this  tumor  among  the  sarcomata 
was  the  observation  that  it  never  appeared  naturally  in  animals 
before  sexual  congress,  and  was  uncommon  in  old  age.  It  showed, 
therefore,  an  age  incidence  different  from  that  of  sarcoma,  the  curve 
for  which  was  similar  to  that  of  carcinoma. 

Bashford  and  his  collaborators  were  inclined  to  describe  the  tumor 
as  a  connective  tissue  reaction  educed  by  a  Hving  virus  still  undis- 
covered, notwithstanding  the  fact  that  the  growth  resembled  the  neo- 
plasms in  its  histological  features,  local  mode  of  origin,  partial  in- 
crease from  its  own  resources,  and  a  Kmit  of  transmission  within  one 
species. 

The  transfer  of  this  tumor  to  dogs  the  authors  had  found  nearly 
always  successful,  no  matter  what  breed  was  inoculated.     A   small 


232  TUMORS    OF    A   NATURE    STILL   UNDECIDED 

proportion  of  the  transmitted  growths  regressed  and  ultimately  dis- 
appeared, and  in  cases  where  this  had  occurred,  as  well  as  in  dogs 
bearing  large  tumors,  re-inoculation  had  succeeded. 

Beebe  and  Ewing  ^  discussed  several  diseases  of  the  dog  which  might 
readily  be  confounded  with  lympho-sarcoma,  and  suggested  that 
more  than  one  malady  had  been  included  in  the  investigations  of  those 
who  had  worked  with  dog  tumors,  and  that  certain  conflicting  obser- 
vations might  find  herein  an  explanation.  They  had  been  unable 
exactly  to  classify  the  growth  While  it  most  nearly  resembled  a 
large  cell  lympho-sarcoma,  the  elements  were  polygonal  more  often 
than  round ;  moreover,  the  fine  reticulum  of  a  lympho-sarcoma  was 
missing,  the  growth  was  much  less  malignant  than  large  cell  lympho- 
sarcoma in  man,  the  arrangement  of  the  cells  in  alveoh  without  lumina 
was  sometimes  distinct,  the  protoplasm  was  nearly  homogeneous, 
and  a  mucinous  discharge  from  the  cut  surface  of  the  tumor  was  char- 
acteristic. The  general  histological  features  suggested  the  diagnosis 
of  alveolar  sarcoma  or  endothelioma. 

The  crucial  point  which  these  authors  attempted  to  settle  was  the 
mode_oLorigin  of  the  transmitted  tumor  —  whether  the  nodules  re- 
sulted from  the  proliferation j3fjnx)c^^  cells  or  were  produced  by 
sjtimulatim  of^^  tissue  elements.     For  the 

purpose  of  deciding  this  question,  grafts  were  removed  at  intervals 
of  from  one  to  twenty-one  days.  After  two  days  peripheral  islands 
of  tumor  cells,  chiefly  normal,  were  found  in  contact  with  small  blood 
vessels  which  seemed  to  belong  to  the  original  tumor,  since  they  con- 
tained healthy  red  blood  cells,  as  though  circulation  had  been  restored 
in  them.  Most  of  these  islands  were  sharply  separated  from  the  host's 
tissues  by  fibrin  or  leucocytes.  After  three  days  the  graft  had  become 
well  fused  with  the  surrounding  subcutaneous  tissue,  and  the  peripheral 
islands  of  intact  cells  were  usually  incorporated  into  a  definite  layer 
surrounding  the  necrotic  center.  In  this  zone  many  blood  vessels  were 
to  be  found,  some  of  which  must  have  belonged  to  the  graft,  as  they 
were  too  large  to  have  developed  in  three  days.  The  outer  margin  of 
the  layer  was  sharply  separated  by  strands  of  fibrin  from  the  neighbor- 
ing tissues,  and  no  trace  could  be  found  of  the  transformation  of  fibro- 
blasts, or  any  other  elements  of  the  host,  into  tumor  cells.     Many  of 

^  Jour.  Med.  Research,  1906,  N.S.,  x,  209. 


TUMORS    OF   A   NATURE    STILL   UNDECIDED 


233 


the  parenchymal  cells  of  the  graft  were  undergoing  mitosis  at  this 
stage.  In  six-day  specimens  areas  were  occasionally  encountered  in 
which  a  minghng  of  fibroblasts  and  tumor  cells  had  taken  place,  but  no 
evidence  could  be  discovered  of  the  conversion  of  fibroblasts  into  malig- 
nant cells.  Such  areas  were,  however,  rare,  and  all  but  small  portions 
of  the  circumference  of  the  graft  Was  from  the  very  first  separated 
from  the  host's  tissues  by  fibrin,  fat,  or  connective  tissue.  In  by  far 
the  greater  part  of  the  growing  mass  the  authors  found  it  impossible 
to  conceive  how  the  malignant  cells  could  have  been  derived  from  the 
elements  of  the  host. 

They  were  forced  to  the  conclusion,  therefore,  that  the  infectious 
lympho- sarcoma  of  dogs  was  a  true  malignant  neoplasm,  the  cells  of 
which  showed,  perhaps,  a  greater  capacity  for  independent  existence 
and  infectivity  than  was  seen  in  any  other  known  tumor  process. 

The  same  authors,^  in  a  discussion  of  the  biology  of  the  tumor  cell, 
gave  a  preliminary  account  of  a  series  of  experiments  designed  to  test 
the  growth  power  of  the  cells  of  this  tumor  in  various  media.  In 
physiological  saline  solution  death  supervened  after  forty-eight  hours 
at  room  temperature.  The  serum  of  a  rabbit  immunized  against  pure 
nucleo-proteid  prepared  from  the  growth  caused  pronounced  agglutina- 
tion, but  preserved  the  cells  considerably  longer  than  did  salt  solution. 
In  sterile  defibrinated  blood  frorh  a  dog  with  growing  tumors  the  cells 
remained  aHve  for  as  long  as  seventy-two  hours,  and  at  the  end  of  this 
period  they  were  apparently  still  capable  of  growth.  At  the  end  of 
forty-eight  hours  they  presented  figures  highly  suggestive  of  karyo- 
kinesis.  When  the  medium  was  changed  every  twelve  hours,  viability 
was  preserved  for  as  long  as  ninety-six  hours,  although  no  evidence  of 
cell  division  was  discernible  after  forty-eight.  In  all  the  experiments, 
the  blood  from  dogs  with  growing  tumors  seemed  to  be  a  more  favorable 
medium  than  that  from  animals  in  which  the  tumor  had  regressed. 

Because  of  the  location  of  the  primary  growths,  and  the  trans- 
missibiUty  of  the  dog  tumor,  Apolant  ^  considered  it  a  granuloma 
rather  than  a  true  malignant  growth,  and  suggested  as  a  possible 
etiological  factor  a  virus  analogous  to  that  of  lues. 

1  British  Med.  Jour.,  1906,  ii,  1559. 

-  Handbuch  d.  path.  Mikroorganismen,  Kolle  u.  Wassermann,  Jena,  1907,  erste  Erganz- 
ungsbaud,  Heft  2,  446. 


234 


TUMORS    OF   A   NATURE    STILL   UNDECLDED 


Wade  ^  recorded  the  transference  of  the  growth  to  two  foxes  and  a 
number  of  dogs.  In  normal  animals  of  the  latter  species  transmission 
was  invariably  successful,  but  those  which  had  been  able  to  rid  them- 
selves of  a  tumor  were  no  longer  susceptible. 

Nodules  excised  at  various  intervals  after  introduction  showed 
that  the  tumor  was  formed  both  from  the  cells  inserted  and  the  ele- 
ments of  the  surrounding  connective  tissue,  the  latter,  under  the 
influence  of  the  tumor  cells,  remaining  immature  and  acquiring  the 
characteristics  of  tumor  cells  instead  of  developing  into  finished 
fibroblasts. 

Examination  of  a  receding  tumor  demonstrated  a  smaller  number- 
of  mitoses  than  that  generally  seen  in  this  growth,  a  peripheral  lami- 
nated border  of  fibrous  tissue,  and  several  hemorrhages.  A  nodule 
removed  from  a  dog  in  which  a  number  of  tumors  had  just  disap- 
peared, was  surrounded  by  a  thick,  laminated  border  of  dense,  fibrous 
tissue  containing  many  polyblasts  and  damaged  tumor  elements, 
while  in  the  central  part  there  was  found  an  enormous  number  of 
polyblasts,  and  an  occasional  degenerating  parenchymal  cell. 

The  lymphocyte  and  its  derivatives  having  been  found  to  play  such 
an  important  part  in  the  hfe  cycle  of  the  tumor,  examination  of  the 
blood  was  undertaken,  and  daily  estimations  made  in  eight  animals 
during  a  period  of  two  months  showed  that  establishment  and  growth 
were  accompanied  by  a  steady  increase  in  the  percentage  of  lympho- 
cytes in  the  circulating  blood. 

The  kidneys  of  twenty- three  animals  were  examined.  Sixteen 
were  dogs  which  had  been  inoculated  with  portions  of  the  tumor, 
five  were  animals  into  which  a  filtrate  had  been  injected,  one  was  a 
dog  that  had  recovered  from  a  sporadic  growth,  and  one  a  fox  in  which 
a  tumor  had  developed  as  the  result  of  implantation.  In  all  these 
animals,  with  but  three  exceptions,  evidence  of  inflammatory  change 
was  present,  the  apparent  age  of  the  lesion  corresponding  closely 
with  the  length  of  the  period  during  which  the  virus  had  been  exerting 
its  action.  The  kidneys  of  six  apparently  healthy  dogs  showed,  on 
the  contrary,  no  sign  of  inflammation. 

Discussing  the  classification  of  the  dog  tumor,  Wade  expressed 
a  preference  for  the  name  infective  sarcoma,  in  the  belief  that  the 

1  J  OUT.  Path,  and  Bad.,  1908,  xii,  384. 


TUMORS    OF   A   NATURE    STILL   UNDECIDED  235 

growth  lay  in  the  borderland  between  the  infective  granulomata  and 
the  true  neoplasms. 

V.  Dungern  ^  attempted  to  elucidate  the  nature  of  the  tumor  by  a 
method  employed  in  conjunction  with  Coca^  in  earlier  investigations 
of  a  hare  sarcoma.  This  tumor  was  able  to  proHferate  in  rabbits  also, 
where  it  produced  antibodies  against  hare  blood,  a  proof  that  the  tissue 
growing  in  the  rabbit  had  been  derived  from  hare  cells.  A  similar 
procedure  appHed  to  the  dog  tumor  growing  in  the  fox  showed  that 
in  all  probability  the  nodule  was  composed  of  elements  produced  by 
the  latter  host,  rather  than  of  cells  from  the  dog.  The  growth  was 
accordingly  not  a  true  blastoma,  but  a  granuloma,  and  presumably 
the  product  of  a  micro-organism.  However,  this  conception  could 
not  be  used  to  support  directly  a  theory  of  the  parasitic  etiology  of 
neoplasms,  for  in  spite  of  a  similarity  in  histological  structure  the  type 
of  growth  exhibited  by  the  dog  tumor  was  enough  to  distinguish  it 
from  the  true  blastomata.  Still,  it  was  evident  that  there  could  exist 
an  infective  agent  able  specifically  to  excite  the  growth  of  certain  cells 
and,  therefore,  that  the  distinction  between  the  genuine  blastomata 
and  the  granulomata  need  not  be  necessarily  absolute. 

As  for  therapeutic  investigations  upon  the  dog  tumor,  Sticker  ^ 
brought  about  partial  regression  through  the  inoculation  of  immune 
serum,  and  cure  by  the  repeated  intravenous  inoculation  of  hve  tumor 
cells.  Salvarsan  also  exerted  a  definite  curative  action,  but  the  effect 
of  atoxyl  was  only  temporary.  Bergell  and  Sticker  '^  announced 
the  disappearance  of  a  tumor  after  treatment  with  liver  ferments. 
Beebe  •'  and  Crile  and  Beebe  ^  were  able  to  cure  tumor-bearing  dogs 
by  bleeding  them  as  completely  as  possible  and  transfusing  them 
with  the  blood  of  immune  dogs,  while  Beebe  and  Tracy  "^  found  that 
certain  bacterial  toxins  exerted  a  destructive  action  upon  the  tumors. 

^  Munch,  med.  Woch.,  191 2,  lix,  238. 

^  Zeitschrift  f.  Immiinitdtsforsch.,  etc.,  Orig.,  1909,  ii,  395. 

^  Zeitschriftf.  Krebsforsch.,  1906,  iv,  269,  310. 

Berl.  klin.  Woch.,  1908,  xlv,  1391. 

Centralbl.  f.  dig.  Bakt.,  etc.,  Erste  Abt.,  Orig.,  1911,  lix,  464. 
*  Deut.  med.  Woch.,  1907,  xxxiii,  1521. 
^  Jour.  American  Med.  Assoc,  1907,  xlix,  1492. 

Jour.  Med.  Research,  1910,  N.S.,  xvii,  389. 
^  Proc.  Soc.  Exp.  Biol,  and  Med.,  1906-1907,  iv,  118. 

Jour.  Med.  Research,  1908,  N.S.,  xiii,  385. 
'^  Jour.  American  Med.  Assoc,  1907,  xlix,  1493. 


236  TUMORS    OF    A    NATURE    STILL    UNDECIDED 

Gaylord  ^  reported  the  successful  treatment  of  the  growths  by  the  in- 
jection into  them  of  uncoagulated  blood  from  immune  dogs,  suggesting 
that  the  apparent  importance  of  preventing  the  blood  from  clotting 
indicated  that  leucocytes  might  play  an  important  role  in  preser\'ing 
the  immune  characteristics  of  the  injected  serum. 

THYROID    ADENO-CARCINOMA    OF    THE    TROUT 

Bonnet^  was  among  the  first  to  describe  this  disease,  not,  however, 
as  a  mahgnant  growth.  Among  the  trout  in  a  hatchery  at  Torbole  on 
the  Gardasee  he  observed  an  epidemic  which  in  four  months  and  a  half  • 
destroyed  not  less  than  three  thousand  fish.  In  the  trout  affected, 
tumors  appeared  on  the  floor  of  the  mouth  and  the  gills,  grew  with  great 
rapidity,  and  determined  the  death  of  the  fish.  In  two  cases  Bonnet 
found  soft,  bluish  red,  smooth  nodules  on  both  sides  of  the  tongue  at 
the  first  and  second  gill-arches,  and  similar,  although  smaller,  confluent 
tumors  ventrally  situated  on  the  gill-arches,  while  in  three  others  the 
lesions  were  hmited  to  the  gills,  and  in  one  case  were  unilateral.  Micro- 
scopic examination,  which  oft"ered  "nothing  characteristic,"  showed  an 
epithehal,  often  tubular  structure,  and  demonstrated  the  presence  of 
bodies  resembhng  lymphoid  cells,  which  Bonnet  took  for  gregarines. 

Purvis,^  in  1888-1889,  discovered  columnar  cell  carcinomata  affect- 
ing the  pharynx  in  two  trout  from  the  Solway  fisheries  in  Scotland. 
According  to  Murray  "*  the  last  epidemic  of  the  disease  in  the  British 
Isles  occurred  in  1888. 

The  disorder  was  next  reported  from  New  Zealand  by  Scott,  Ayson, 
Gilruth,  and  Wilkie.'^  Scott  discussed  a  form  of  tumor  prevalent 
among  the  American  brook  trout  in  the  New  Zealand  hatchery,  which, 
originating  in  the  middle  line  of  the  ventral  wall  of  the  pharynx,  ex- 
tensively involved  the  gill-arches.  Upon  microscopic  examination 
Scott  found  that  there  took  place  at  first  a  prohferation  of  the  cells  in 

1  Jour.  American  Med.  Assoc.,  1909,  lii,  411. 

2  Bayerische  Fischereizcitung,  1883,  Xo.  6,  79.  (As  this  publication  was  inaccessible  in 
this  country,  Bonnet's  account  has  been  taken  from  Pick's  excellent  monograph.) 

^  Cited  by  Bashford  and  ^lurray,  Sci.  Reports,  Cancer  Research  Fund,  London,  1904, 
No.  I,  9. 

*  Third  Sci.  Report,  Imperial  Cancer  Research  Ftind,  London,  1908,  52. 

5  Reports  of  the  New  Zealand  Department  of  Agriculture,  Division  of  Veterinary  Science, 
1891  and  1901-1902  ;   cited  by  Pick. 


TUMORS    OF   A   NATURE    STILL   UNDECIDED 


237 


the  acini  (the  organ  was  not  mentioned),  and  secondarily  a  destruction 
of  boundaries  which  permitted  an  outgrowth  of  cells,  and  that  these 
elements,  infiltrating  the  stroma,  finally  produced  a  true  carcinoma. 
Ayson  encountered  three  cases  of  this  "gill  disease"  in  1890  among 
American  brook  trout,  and  later  among  rainbow  and  other  trout. 
The  disorder  occurred  invariably  in  certain  hatcheries  and  always 
among  certain  kinds  of  salmonoid  fish.  Gilruth  received  from  Ayson 
three  rainbow  trout,  each  with  a  reddish  soft  tumor  the  size  of  a  large 
walnut  and  involving  the  first  and  second  gill-arches.  The  smaller 
alveoli  were  clothed  with  cylindrical  or  cubical  epithelium,  while  the 
larger  were  lined  with  a  single  layer  of  columnar  epithelium  and  con- 
tained cubical,  more  or  less  degenerated  elements  in  the  center.  The 
capsule  and  the  stroma  carried  wide,  thin-walled  blood  vessels,  and 
hemorrhages  were  frequently  encountered. 

Marianne  Plehn  ^  described  the  disease  in  the  trout  and  the  char, 
several  affected  specimens  of  which  had  been  discovered  in  hatcheries 
and  sent  into  the  laboratory  during  the  preceding  few  years.  The 
tumors  were  in  the  neighborhood  of  the  lower  jaw,  involving  both 
mouth  and  throat,  and  were  firm  while  still  of  small  size,  but  became 
softer  as  the  process  advanced.  In  fish  bearing  tumors  of  consider- 
able size  the  jaws  were  not  infrequently  forced  apart,  a  condition 
which  led  to  grave  interference  with  both  respiration  and  the  intake  of 
nourishment.  These  growths,  which  microscopic  examination  showed 
to  be  adeno-carcinomata,  arose  in  the  thyroid  and  presented  at  first 
a  structure  simulating  the  normal  gland,  the  cancerous  nature  of  the 
affection  remaining  masked  until  a  later  period  when  it  displayed  itself 
by  invasion  and  destruction  of  bone  and  muscle. 

Hofer  ^  described  the  disorder  under  the  name  of  malignant  goiter, 
or  adeno-carcinoma  of  the  thyroid,  and  reported  instances  among  lake 
trout  living  in  a  state  of  nature  in  the  Mondsee.  Of  the  causation  of 
this  rare  disease  nothing  was  known,  and  no  parasite  had  been  dis- 
covered which  could  be  brought  into  etiological  relationship  with  it. 

Jaboulay  ^  studied  six  trout  with  thyroid  adeno-carcinomata  invading 

^  Allg.  Fischerei-Zeitung,  1902,  xxvii,  117. 
^  Handbuch  der  Fischkrankheiten,  Munich,  1904,  191. 
^  Lyon  med.,  1908,  ex,  335. 
Province  med.,  1908,  xix,  186. 


238  TUMORS    OF   A   XATOIE    STILL   L"XDECLDED 

all  the  tissues  in  the  neighborhood  of  the  gland  and.  in  an  advanced 
stage,  invohdng  even  distant  organs.  In  the  opinion  of  this  author 
the  disease,  which  was  both  hereditary  and  contagious,  was  the  out- 
come of  infection  ^ith  mA-xosporidia. 

Pick  and  Poll  ^  described  a  thyroid  tumor  of  the  trout,  glandular 
in  structure  throughout  its  early  stages,  but  possessing  the  character- 
istics of  a  medullary  carcinoma  when  more  advanced. 

Pick  himself  ^  published  a  much  fuller  description  of  the  disease  about 
two  years  later.  That  it  was  not  of  equal  distribution  was  shown  by 
the  fact  that,  in  spite  of  reported  epidemics  in  other  parts  of  the  world, 
the  disorder  was  totally  unknown  in  Xorth  and  ^Middle  Germany,  while 
in  the  southern  part  of  the  country  only  sporadic  cases  had  been  en- 
countered. The  tumors  were  indubitably  carcinoma ta  with  the 
power  of  infiltrating  and  de5tro}-ing  neighboring  tissues,  although  they 
varied  in  structure  from  parench}'matous  goiter  to  medullary  or 
scirrhous  carcinoma.  Histological  appearance  was.  however,  no  guide 
to  chnical  behaAior.  and  those  growths  which  looked  most  benign 
were  not  infrequently  found  to  infiltrate  most  seriousl}'.  Pick  had 
never  seen  any  metastatic  deposits,  if  one  doubtful  instance  were 
excepted,  although  he  confessed  that  the  search  had  not  been  by 
any  means  so  careful  as  that  which  had  been  prosecuted  upon  neo- 
plasms of  the  mouse.  The  tumors  originated  in  the  thyroid  gland,  as 
was  clea'.iy  shown  by  their  location  and.  above  all,  by  their  architec- 
ture, and  no  variety  of  salmonoid  fish  hA-ing  in  hatcheries  was  exempt, 
although  the  growths  were  often  curiously  limited  to  one  species  in  a 
hatchery,  as  when,  for  example,  where  Salmo  iridens  and  S.  fontinalis 
were  both  kept,  only  the  former  was  affected.  On  the  other  hand,  in 
a  neighboring  hatchery  neither  might  be  spared.  Again,  certain 
ponds  would  be  found  to  contain  affected  fish  while  in  others  the 
trout  remained  free  from  the  disorder.  The  disease  attacked  chiefly 
fish  over  two  years  old.  and  from  2%  to  7%  of  those  exposed  fell  vic- 
tims to  it.^  Pick  did  not  see  any  necessity  for  implicating  parasites 
in  the  etiology  of  the  disease  or  for  assuming  that  the  carcinoma,  as 

^  Berl.klin.  Woch.,  1903,  xl,  547. 
^  Berl.  Mill.  Woch.,  1905,  xlii,  1435,  1477,  149S,  1532. 

'  According  toPlehn  {Travaux  dela  deuxieme  Conference  internal,  pour  F Etude  du  Cancer, 
Paris,  1911,  227)  70%  of  the  fish  in  a  pond  ma}  be  affected. 


TUMORS    OF    A    XATUEE    STILL    UNDECIDED  239 

such,  was  endemic.  Reasoning  from  what  was  known  of  human  cases 
it  was  very  probable  that  in  the  trout  the  primary  lesion  was  a  simple 
endemic  goiter  evolved,  perhaps,  by  some  condition  of  the  water,  and 
that  the  mahgnant  prohferation  was  secondary  to  this  lesion. 

V.  Hansemann  ^  expressed  the  opinion  that,  in  spite  of  the  absence 
of  metastases,  there  could  be  but  Httle  doubt  of  the  carcinomatous 
nature  of  the  tumor  which  Pick  had  described. 

Plehn  -  was  unable  to  accept  the  water  of  the  hatchery  as  an  etio- 
logical factor,  for  only  one  of  two  kinds  of  trout  in  the  same  pond  might 
be  affected,  while,  furthermore,  the  disease  might  disappear  after 
ha\Tng  involved  a  hatchery  for  seA-eral  years,  and  this  ^^•ithout  any 
change  ha\"ing  been  made  in  the  water.  To  explain  the  causation  of  the 
disease  there  remained,  in  addition  to  a  parasitic  h\pothesis,  the  assump- 
tion that  all  affected  fish  were  the  descendants  of  a  few  groups  of  parents, 
and  that  hereditary  influence  was  a  powerful  predisposing  factor. 

Gaylord  ^  pubhshed  a  prehminary  description  of  an  epidemic  among 
two-year-old  brook  trout  and  bro\\m  trout.  At  the  hatchery  in  ques- 
tion, water  was  supphed  from  a  spring  issuing  from  a  hillside  and 
emptying  into  a  pond,  to  be  piped  from  there  to  a  small  reservoir  and 
finally  through  a  series  of  tanks.  Carcinoma  of  the  thyroid  had  been 
discovered  among  the  fish  in  this  pond  two  years  pre\'iously.  and  a 
year  later  the  pond  was  emptied  and  re-stocked  \sath  young  fish.  One 
of  the  tanks  fed  from  the  water  passing  through  this  pond,  and  hold- 
ing nearly  four  thousand  two-year-old  brook  trout  raised  from  eggs 
procured  at  a  hatchery  where  the  chsease  was  not  known  to  exist,  con- 
tained seven  hundred  fish  in  various  stages  of  the  disorder.  In  an 
adjoining  tank,  which  had  no  connection  whatsoever  \\dth  the  one  in 
question,  there  were  two  hundred  bro^^^l  trout  reared  from  eggs 
hatched  on  the  premises ;  of  these,  from  3%  to  4%  were  affected. 
The  infected  fish  had  at  no  time  come  into  direct  contact  \\-ith 
those  in  the  upper  pond,  where  it  was  knowm  that  the  disease  had 
existed,  neither  had  the,  brook  trout  and  the  bro\\Ti  trout  been  at  any 
time  in  contact  \\dth  each  other.  Gaylord  believed  that  the  condi- 
tions discovered  in  the  hatchery  under  discussion  pointed  very  strongly 
to  the  infectious  nature  of  this  form  of  cancer,  and  to  the  suggestion 

^  Berl.  Mill.  Woch.,  1905,  xlii,  1542.  -  Zeitschrift  f.  Krebsforsch.,  1906,  iv,  560. 

^  Jour.  American  Med.  Assoc,  1909,  Hi,  411. 


240  TUMORS    OF    A    NATURE    STILL   UNDECIDED 

that  the  contagion  was  water  borne.  It  was  possible  that  in  this  in- 
stance the  feeding  of  liver  was  in  some  way  connected  with  the  out- 
break, for  in  another  hatchery,  where  this  material  had  been  replaced 
by  chopped  sea  fish,  the  disease  had  disappeared  entirely,  although 
formerly  it  had  been  endemic. 

Continuing  his  report,  Gaylord  ^  described  a  fish  with  carcinoma  of 
the  th}Toid  and  a  similar  growth  on  the  lower  jaw,  a  distribution  which 
made  it  plain  either  that  the  tumor  could  metastasize  or  that  it  was 
transplantable.  Analysis  showed  that  trout  occupying  ponds  which 
received  water  from  those  containing  cases  of  the  disease  might  be- 
come affected,  although  a  great  many,  and  more  particularly  hybrids, 
were  immune.  The  disease  attacked  fish  both  large  and  small  and, 
especially  in  the  former,  spread  rapidly,  eroding  the  bone,  destroying 
the  cartilage,  and  infiltrating  the  muscle.  The  tumors  showed  varying 
characteristics,  frequently  retaining  the  alveolar  type  with  colloid 
or,  again,  shomng  a  structure  strictly  adenomatous;  but  in  all  cases 
there  were  areas  which  presented  the  features  of  soHd  carcinoma. 

In  the  discussion  of  this  paper  Stockard  ^  pointed  out  that  many  of 
the  infiltrative  phenomena  in  the  aft'ected  thyroid  might  be  due  to  the 
fact  that  the  gland  was  not  encapsulated,  and  that  smaU  foUicles  often 
appeared  among  the  muscle  fibres  and  loose  tissues  of  the  branchial 
region.  On  the  same  occasion  Gudernatsch  offered  an  account  of 
the  normal  thyroid  gland  of  the  Teleostei.  This  was  not  a  compact, 
uniform  organ  as  it  was  in  mammals,  but  was  broken  up  into  numerous 
single  folhcles,  the  distribution  varying  not  only  with  the  species  but 
with  the  individual.  The  folhcles  were  generally  most  densely  packed 
around  the  ventral  aorta  and  its  branches  to  the  gills,  while  toward  the 
periphery  the  arrangement  became  less  close  until  the  foUicles  lay 
completely  separated.  Their  distribution  extended  as  far  as  the  neigh- 
boring structures  would  allow  and  they  even  invaded  other  tissues, 
reaching  out  laterally  along  the  gill  arteries  and  sometimes  even  pene- 
trating the  gills.  A  more  detailed  description  of  this  gland  in  the  fish 
may  be  found  in  two  papers  by  Gudernatsch  ^  and  in  the  article  by 

1  Jour.  American  Med.  Assoc,  1910,  liv,  227. 
'^  Jour.  American  Med.  Assoc,  1910,  liv,  227. 
^  Jour.  Morphol.,  1910,  xxi,  709. 
Johns  Hopkins  Hasp.  Bull.,  1911,  xxii,  152. 


TUMORS    OF   A   NATURE    STILL   UNDECIDED  24 1 

Maurer/  who  was  the  first  fully  to  describe  the  diffuse  arrangement  of 
the  thyroid  gland  in  the  fish,  although  Baber  ^  had  previously  men- 
tioned a  few  detached  vesicles  in  the  thyroid  of  the  skate. 

According  to  Ewing,^  while  the  diffuse  condition  of  the  gland  did 
not  affect  the  conclusion  that  genuine  thyroid  tumors  did  arise  in  some 
fish,  it  indicated  that  the  local  extensions  of  these  growths  were  not 
always  to  be  regarded  as  signs  of  metastasis  and  malignancy.  He  ^ 
considered  it  highly  improbable  that  the  disease  was  parasitic  in  its 
origin. 

Gaylord  ^  thought  that  the  non-encapsulation  of  the  gland  would 
not  account  for  the  infiltration  of  vessel  walls,  bone,  and  cartilage 
seen  when  the  growth  had  reached  the  status  of  carcinoma.  He  had 
found  the  disease  endemic  in  probably  not  less  than  75%  of  the  hatch- 
eries containing  salmonoids  throughout  the  United  States,  and  epi- 
demic from  time  to  time,  and  had  observed  a  certain  variation  in  the 
severity  of  the  disease  and  in  the  characteristics  of  the  lesions  in  differ- 
ent epidemics.  Thus,  in  one  hatchery,  more  than  50%  of  the  tumors 
presented  the  structure  of  carcinoma,  while  in  an  epidemic  encountered 
the  following  year  in  another  locaHty  the  growths  were  more  like  simple 
goiters.  If  the  disease  started  in  the  uppermost  tanks,  it  progressed 
with  the  course  of  the  water  through  the  lower  ones,  and  the  percentage 
of  infected  fish  increased  from  above  downward ;  but  where  it  occurred 
low  down  it  had  never  been  found  to  proceed  upward  against  the 
stream.  About  50%  of  fish  taken  from  infected  pools  and  placed  under 
better  hygienic  conditions  would  recover,  although  spontaneous  cure 
occurred  also  in  tanks  where  the  disease  was  in  progress.  Fish  in 
which  tumors  had  disappeared  did  not  acquire  the  disease  a  second 
time,  and  entire  groups  had  been  observed  to  resist  attack,  but  whether 
through  possession  of  natural  immunity  or  through  a  condition  of 
resistance  conferred  by  previous  recovery,  had  not  yet  been  deter- 
mined. Muddy  water  from  the  most  infected  ponds  produced  goiter 
in  dogs  after  five  weeks  and  caused  marked  enlargement  of  the  thy- 
roid in  rats. 

^  Mdrphol.  Jahrb.,  1886,  xi,  129. 

^  Philosoph.  Trans.  Roy.  Soc.  London,  1881,  clxxii,  580. 

'  Jour.  American  Med.  Assoc,  1910,  liv,  228.  "•  Arch.  Internal  Med.,  1908,  i,  176. 

^  TravaiLv  de  la  deuxieme  Conference  internal,  pour  V Elude  du  Cancer,  Paris,  1911,  787. 


242  '         TUMORS    OF   A   NATURE    STILL   UNDECIDED 

Marine  and  Lenhart  ^  undertook  experiments  designed  to  discover 
any  possible  connection  between  the  ordinary  goiter  (active  thyroid 
hyperplasia)  of  fish  and  animals,  and  the  so-called  cancerous  affection 
of  the  thyroid.  For  the  reasons  that  young  fish  were  more  affected 
than  old,  that  the  hyperplasia  was  checked  by  the  addition  of  Lugol's 
solution  to  the  water  in  the  tank,  that  the  removal  of  fish  to  an  open 
brook  effected  a  cure,  that  the  chnical  incidence  of  tumors  was  in  close 
relation  with  the  supply  of  water,  and  finally,  because  the  severity  of 
the  disease  as  determined  by  histological  examination  was  also  directly 
related  to  the  water  supply,  these  authors  could  not  accept  the  pre- 
vailing opinion  that  the  disease  was  true  cancer.  On  the  contrary, 
they  believed  it  to  be  an  extreme  illustration  of  endemic  goiter,  the 
end  stage  of  which  was  cretinism.  All  phases  of  the  lesion  reacted  to 
iodine,  the  mild  degrees  more  rapidly  than  the  severer,  and  the  dis- 
order in  its  earlier  stages  underwent  involution  after  from  two  to  three 
weeks  of  treatment,  although  at  later  periods  one  or  two  months  might 
be  necessary.  The  iodine  reaction  was  a  specific  test  for  functional 
hyperplasia,  since  it  did  not  occur  in  the  case  of  true  tumors.  As  the 
authors  had  been  unable  to  find  any  point  in  the  course  of  the  disease 
under  consideration  at  which  it  did  not  yield  to  iodine,  they  concluded 
that  there  was  no  stage  which  could  be  looked  on  biologically  as  cancer. 
Although  they  had  been  unable  to  transmit  the  disease  by  grafts  from 
one  fish  to  another,  they  did  not  consider  that  their  technic  had 
reached  a  degree  of  perfection  sufficient  to  permit  the  conclusion  that 
the  affected  tissue  was  not  transplantable.  They  had  never  observed 
secondary  growths,  with  the  exception  of  two  doubtful  tumors  in  the 
gills  and  in  the  lower  lip,  but  it  was  questionable  whether  nodules  in 
these  locations  might  not  be  due  to  hyperplasia  of  existing  anlagen. 
There  was  no  evidence  that  the  disorder  was  either  infectious  or  con- 
tagious, but  much  in  favor  of  the  view  that  it  was  the  symptomatic 
manifestation  of  a  metabolic  and  nutritional  disturbance. 

There  were  three  major  conditions  which,  in  some  way  still  obscure^ 

^  Jour.  Exp.  Med.,  1910,  xii,  311. 
Johns  Hopkins  Hasp.  Bull.,  1910,  xxi,  95. 
Bull.  No.  7,  Dept.  Fisheries,  Pennsylvania,  Harrisburg,  1910. 
Jour.  Exp.  Med.,  191 1,  xxii,  455. 
Bull.  No.  8,  Dept.  Fisheries,  Pennsylvania,  Harrisburg,  1911. 


TUMORS  OF  A  NATURE  STILL  UNDECIDED  243 

influenced  the  thyroid  growth  :  Limited  water  supply,  overcrowding, 
and  overfeeding  with  a  highly  artificial  and  incomplete  food.  The 
water  of  the  hatchery  was  not  intrinsically  goiter-producing,  because 
fish  would  not  develop  the  disease  unless  at  least  the  factor  of  over- 
feeding with  an  incomplete  food  were  in  operation,  and  because  they 
recovered  if  the  overfeeding  and  overcrowding  were  corrected,  even 
though  remaining  in  the  same  pond.  Therefore  it  seemed  probable 
that  food  was  the  major  factor  in  bringing  about  some  fault  of 
nutrition  favorable  to  goiter  development,  although  it  was  impossible 
to  suggest  what  elements  in  the  diet  were  impHcated. 

That  the  thyroid  was  an  extremely  labile  organ,  reacting  quickly  to 
relatively  sHght  variations  in  the  body  metaboHsm  and  even  showing 
a  slight  daily  histological  change,  has  been  frequently  emphasized  by 
these  authors ;  ^  and  while  they  found  that  thyroid  changes  did  not 
take  place  in  fish  so  rapidly  as  in  mammals,  the  range  of  histological 
variation  was  nevertheless  equally  wide. 

Gaylord  -  was  able  to  substantiate  the  action  of  iodine  upon  the 
thyroid  as  described  by  Marine  and  Lenhart,  and  found  that  affected 
fish  kept  in  running  water  to  which  potassium  iodide  was  continu- 
ously added  in  a  concentration  of  one  to  five  milHon,  showed  distinct 
histological  changes  after  a  few  days.  They  were  similar  to  those 
described  by  the  authors  just  cited,  and  consisted  in  e\^dences  of  ces- 
sation of  active  proHferation  on  the  part  of  the  glandular  disease,  flat- 
tening of  the  epithelium,  and  the  presence  of  colloid  within  the  alveoli. 
But  Gaylord  discovered  that  bichloride  of  mercury  in  the  same  con- 
centration would  produce  all  these  alterations  more  effectively  and  in 
less  time,  and  described  a  tumor  of  seven  millimeters  diameter  which 
disappeared  completely  in  the  course  of  forty  days'  exposure  to  mer- 
cury. Hence  he  concluded  that  the  action  of  iodine  upon  the  thyroid 
was  not  specific.  In  the  observations  that  the  disease  was  of  epidemic 
occurrence,  that  its  incidence  increased  with  the  flowing  of  water  from 
pond  to  pond,  that  it  was  ''created"  in  certain  ponds  and  that  it  was 
not  a  result  of  the  original  constituents  of  the  water,  that  fish  recovered 
spontaneously  and  were  then  immune,  that  the  disorder  could  be 
markedly  influenced  and  perhaps  cured  by  iodine  and  mercury,  both 

^  Johns  Hopkins  Hasp.  Bull.,  1911,  xxii,  217. 

^  Travanx  de  la  deuxieme  Conference  internal,  pour  V Etude  du  Cancer,  Paris,  191 1,  789. 


244  TUMORS   OF   A   NATURE    STILL   UNDECIDED 

well-known  antiseptics,  Gaylord  saw  evidence  to  support  the  conten- 
tion that  the  disease  was  infectious. 


TRANSMISSIBLE    SARCOMA    OF    THE    FOWL 

Fujinami  and  Inamoto  ^  described  in  1 910  a  spontaneous  connective 
tissue  neoplasm  of  the  hen,  probably  a  myxoma  or  a  myxo-sarcoma, 
which  was  so  readily  transplantable  that  inoculation  had  been  almost 
invariably  successful.  Spontaneous  absorption  was  relatively  com- 
mon and  seemed  to  depend  upon  some  special  condition  of  the  host._ 
In  the  case  of  transplanted  tumors  metastases  were  discovered  in  the 
skin,  eyeHd,  lung,  heart,  Hver,  kidney,  and  intestinal  wall.  At  the 
time  of  writing,  the  neoplasm  had  reached  its  twentieth  generation 
without  any  essential  change  in  its  histology  having  occurred,  and 
there  was  no  evidence  to  support  the  hypothesis  of  parasitic  etiology. 
Growth  power  was  abolished  by  boiling,  but  not  by  a  two  hours'  ex- 
posure to  50°  C.  or  -15°  to  -20°  C,  or  by  grinding  the  cells  in  a  mortar 
with  sand.  The  action  of  antiseptics  for  from  one  to  eighty  minutes 
was  fatal. 

Another  transmissible  tumor  has  been  described  since  then  by 
Rous  -  in  a  young  barred  Plymouth  Rock  hen  of  Hght  color  and  pure 
blood.  First  noticed  when  the  bird  was  about  fifteen  months  old  and 
approximately  two  months  before  she  was  brought  into  the  laboratory, 
the  neoplasm  had  developed  slowly  until,  when  first  seen  by  Rous,  it 
appeared  as  a  large,  irregularly  lobular  mass  projecting  sharply  from 
the  right  breast.     This  growth  was  removed  by  operation  and  frag- 

1  Verhandl.  dcr  japanischen  path.  Gesellsch.,  1911,  erste  Tagung,  114. 
"^  Jour.  Exp.  Med.,  1910,  xii,  696. 

Jour.  American  Med.  Assoc,  1910,  Iv,  1805. 

Jour.  American  Med.  Assoc,  1911,  Ivi,  198. 

Proc.  American  Philosophical  Soc,  1912,  li,  201. 
See  also  Rous  and  Murphy. 

Jour.  American  Med.  Assoc,  191 1,  Ivi,  741. 

Jour.  Exp.  Med.,  191 2,  xv,  119. 

Jour.  Exp.  Med.,  1912,  xv,  270. 

Jour.  American  Med.  Assoc,  191 2,  Iviii,  1938; 
and  Rous,  Murphy,  and  Tytler. 

Jour  American  Med.  Assoc,  1912,  Iviii,  1751. 

Jour.  American  Med.  Assoc,  1912,  Iviii,  1840. 


TUMORS    OF   A   NATURE    STILL   UNDECIDED  245 

ments  of  it  were  at  once  inoculated  with  a  trocar  into  the  opposite 
breast  and  the  peritoneal  cavity  of  the  host,  and  into  two  other  hens  from 
the  same  setting  of  eggs.  Upon  section  the  tumor  was  found  to  have 
undergone  widespread  coagulation  necrosis  at  the  center,  although  it 
had  a  margin  of  translucent,  rather  friable,  yellowish  pink  tissue  with 
a  glistening,  finely  striated  surface.  Microscopically  the  tumor  sug- 
gested sarcoma.  Thirty-five  days  after  implantation,  the  host  was 
dead  of  intraperitoneal  growths,  and  in  the  breast  of  one  of  the  in- 
oculated fowls  a  large  nodule  had  developed. 

Microscopic  examination  of  the  original  growth  and  of  the  nodules 
occurring  elsewhere  in  the  host  following  implantation,  showed  them 
to  be  sarcomata  composed  of  loose  bundles  of  spindle  cells,  crossing  in 
every  direction  and  separated  from  the  smaller  blood  vessels  only  by 
endothelium,  a  structure  which  was  reproduced  with  great  fidelity 
in  all  the  growths  of  subsequent  generations.  Intercellular  fibrils 
were  demonstrable  with  Mallory's  phosphotungstic  acid  stain,  but 
they  were  rare  in  the  more  cellular  portions  of  the  growth.  The  areas 
of  necrosis  seemed  to  be  dependent  in  general  upon  insufficient  vas- 
cularization, although  hemorrhages  from  thin-walled  blood  vessels 
were  occasionally  responsible  for  their  production.  In  spite  of  a 
fairly  well  marked  capsule  the  growth  showed  a  certain  tendency  to 
infiltrate,  not  so  actively,  however,  as  did  its  daughter  tumors.  Re- 
peated bacteriological  examination  yielded  negative  results,  and  the 
growth  was  not  transmissible  to  pigeons,  ducks,  rats,  mice,  guinea- 
pigs,   or  rabbits. 

The  daughter  tumors  throve  at  first  only  in  intimately  related  fowls 
of  the  pure  stock  in  which  the  spontaneous  neoplasm  had  been  dis- 
covered, but  later  transplantations  into  similar  fowls  of  pure  blood 
from  another  source  were  successful,  and  the  tumor  finally  came  to 
grow  in  about  80  to  100%  of  pure  bred,  hght-barred  Plymouth  Rocks, 
and  in  an  occasional  individual  that  showed  by  its  plumage  the  shght 
admixture  of  some  darker  strain.  Contrasted  with  this  outcome  was 
that  obtained  in  the  first  four  generations,  where  the  number  of  suc- 
cessful transplantations  was  but  three  in  twelve.  It  was  never  pos- 
sible to  propagate  the  tumor  in  any  breed  except  Plymouth  Rocks,  and 
proliferation  was  especially  active  in  young  birds.  The  re-inoculation 
of  fowls  that  had  proved  refractory  to  implantation  was  uniformly 


246  TUMORS    OF   A   NATURE    STILL   UNDECIDED 

unsuccessful.  Growth  became  so  vigorous  in  the  later  generations 
that  a  fragment  of  from  one  to  two  millimeters  in  diameter  might 
give  rise  within  three  weeks  to  a  nodule  having  an  average  diameter 
of  about  eight  millimeters,  and  retrogression  of  a  developed  tumor, 
fairly  frequent  at  first,  became  a  rare  event  save  in  cases  where  the 
host  was  ill.  While  the  growths  obtained  from  the  first  inoculation 
required  seventy-one  days  to  reach  an  average  diameter  of  about  four 
centimeters,  and  to  affect  seriously  the  health  of  the  host,  tumors  be- 
longing to  later  generations,  and  the  product  of  a  similar  mode  of  inocu- 
lation, attained  an  average  diameter  of  about  nine  centimeters  three 
weeks  after  the  implantation  of  a  fragment  two  millimeters  in  diameter^ 
and  frequently  determined  a  fatal  issue  in  from  twenty-six  to  thirty 
days.  In  the  seventh  generation,  the  average  time  required  after 
inoculation  for  the  development  and  dissemination  of  secondary 
nodules  was  approximately  one-half  of  that  demanded  in  the  third. 

Metastasis,  which  occurred  by  way  of  the  blood  stream  and  but 
rarely  through  the  lymphatics,  was  more  frequently  observed  in  the 
later  than  in  earUer  generations,  and  secondary  nodules  were  encoun- 
tered less  often  in  the  heart  than  previously,  but  more  commonly  in 
the  hver,  while  the  spleen,  exempt  until  the  seventh  generation,  con- 
tained secondary  deposits  at  that  period  in  two  cases  out  of  twenty- 
five,  and  was  thereafter  frequently  involved. 

In  a  study  of  early  stages  it  was  found  that  during  the  first  forty- 
eight  hours  the  tumor  fragment,  unchanged  in  appearance,  occupied 
a  rent  in  the  host's  tissues  surrounded  by  exudation  and  a  moderate 
accumulation  of  polymorphonuclear  leucocytes.  The  connective 
tissue  of  the  host  was  edematous  at  the  torn  margin,  its  blood  vessels 
dilated,  and  toward  the  end  of  "the  period  under  description  fibroblasts 
and  macrophages  appeared.  During  the  third  day  the  graft  often 
united  at  one  or  more  points  with  the  host's  tissues,  and  although  it 
still  remained  un vascularized,  prohferation  was  in  active  progress, 
cell  division  taking  place  chiefly  by  amitosis,  and  the  fragment  was  not 
infrequently  much  increased  in  size.  Its  loose  structure  facihtated 
nourishment  by  a  direct  interchange  of  fluids,  but  unless  the  graft 
were  broken  or  of  very  small  size  necrosis  took  place  at  its  center. 
The  polymorphonuclear  leucocytes  commenced  to  disappear  at  this 
time  and  fibroblasts,  macrophages,  and  an  abundant  supply  of  newly 


TUMORS    OF   A   NATURE    STILL   UNDECIDED  247 

formed  capillaries  took  their  place.  In  some  fowls  small  round  cells, 
histologically  identical  with  the  lymphocyte,  collected  in  Hmited  num- 
ber, localizing  at  points  where  the  implantation  had  become  attached 
to  the  surrounding  connective  tissue,  but  in  very  susceptible  hosts 
this,  like  all  cellular  reaction,  might  be  absent.  By  the  fourth  day  or 
later  the  fragment  had  increased  greatly  in  size,  vascularization  was 
accomplished,  and  establishment  of  the  nodule  might  be  considered 
perfect.  Even  before  this  period,  however,  tumor  cells  were  often 
discovered  invading  the  tissues  of  the  host  at  points  where  these  were 
in  contact  with  the  graft,  proliferating  strands  of  spindle  cells  extending 
into  the  normal  structures  and  utilizing  for  their  support  the  blood 
vessels  and  connective  tissue  already  present.  The  activity  of  the 
neoplastic  cells,  once  the  tumor  had  become  established,  was  startling, 
and  as  many  as  46%  had  been  found  in  process  of  segmentation  at  one 
time,  of  which  42%  were  in  amitotic  and  4%  in  mitotic  division.  It 
was  not  necessary  for  the  development  of  tumor  fragments  that  they 
be  brought  directly  into  contact  with  the  connective  tissue  of  the  host, 
for  grafts  placed  in  the  peritoneal  cavity  might  establish  themselves 
in  spite  of  its  endothelial  lining,  proliferating  sometimes  in  a  way  to 
suggest  cell  cultures  in  a  fluid  medium  and  at  length  obtaining  a 
blood  supply  from  the  underlying  tissues. 

In  naturally  immune  fowls,  or  in  those  with  acquired  resistance, 
the  phenomena  in  action  about  the  tumor  fragment  did  not  differ 
during  the  first  forty-eight  hours  from  those  in  susceptible  hosts. 
Following  this  period  death  of  the  graft  took  place  in  one  of  two  ways. 
(a)  The  fragment  often  remained  for  many  days  unvascularized  and 
almost  unattached  to  the  surrounding  tissues,  and  underwent  a  gradual 
necrosis  in  which  the  marginal  cells  were  the  last  to  succumb.  These 
elements  might  live  for  a  week  or  ten  days  and  might  even  multiply 
at  first  to  some  extent,  but  they  did  not  invade  the  connective  tissues 
at  those  points  where  they  were  in  contact  with  them.  Meanwhile 
leucocytes  disappeared ^  fibroblasts  and  macrophages  were  substituted, 
lymphocytes  in  small  numbers  infiltrated  the  zone  of  living  tumor,  and 
by  the  end  of  two  weeks,  as  a  rule,  the  graft  was  wholly  necrotic  and 
reorganization  under  way.  (b)  More  frequently  the  implantation 
increased  in  size,  invaded  the  tissues  of  the  host,  and  became  vascu- 
larized with   the  same  rapidity  as  in  susceptible  fowls,  but   imme- 


248  TUMORS    OF   A   NATURE    STILL   UNDECIDED 

diately  upon  its  obtaining  a  foothold  a  lymphocytic  reaction 
supervened  in  the  surrounding  tissues,  so  intense  in  character  that 
even  by  the  fifth  day  the  graft  might  be  embedded  in  a  mass  of 
small  round  cells  six  to  eight  times  its  own  diameter.  A  certain 
degree  of  infiltration  of  the  fragment  occurred  during  this  period,  and 
despite  its  blood  supply  the  tumor  tissue  was  already  degenerated. 
These  two  sets  of  phenomena  leading  to  the  death  of  the  implanted 
fragment  might  both  be  discovered  in  one  host,  an  observation  sug- 
gesting that  their  incidence  was  largely  determined  by  local  conditions. 

The  death  of  the  implantations  could  not  be  ascribed  to  their  fail- 
ure to  acquire  a  supporting  and  vascular  stroma,  as  Bashford  and  Rus- 
sell had  assumed  in  explanation  of  the  death  of  grafts  in  hosts  with 
acquired  resistance,  for  in  by  far  the  greater  number  of  unsuccessful 
transplantations  vascularization  actually  occurred,  although  it  ex- 
isted for  a  brief  period  only.  The  authors  agreed  with  DaFano  re- 
garding the  significance  of  the  lymphocyte  for  immunity.  In  the  case 
of  the  fowl,  however,  the  lymphocytic  response  was  more  vigorous 
than  in  mammals,  possibly  for  the  reason  that  the  lymphocyte  not 
infrequently  constituted  over  40%  of  the  white  cells  in  normal  indi- 
viduals and,  furthermore,  because  this  type  of  cell  responded  to  cer- 
tain processes  more  actively  in  the  fowl  than  in  mammals.  No  gen- 
eral lymphocytosis  accompanied  the  local  reaction  surrounding  the 
tumor. 

It  v/as  found  that  the  sarcoma  could  be  transmitted  after  an  emul- 
sion had  been  passed  through  a  Berkefeld  filter  (No.  5  medium)  im- 
permeable to  B.  prodigiosus,  or  by  means  of  the  dried  and  powdered 
neoplastic  tissue.  Growths  resulting  from  the  inoculation  of  a  fil- 
trate were  much  longer  in  making  their  appearance  than  where  grafts 
had  been  deposited  in  the  ordinary  way,  not  a  trace  of  tumor  being 
palpable  for  from  ten  days  to  three  weeks,  while  subsequent  prolifera- 
tion went  on  more  slowly  than  in  control  tumors. 

The  growths  following  upon  injection  of  a  filtrate,  which  were  first 
noticeable  as  minute  nodules  at  some  point  in  the  need^a  track,  de- 
veloped in  only  a  small  number  of  inoculated  fowls ;  but  when  the 
causative  agent  was  introduced  in  the  form  of  dried  powder  suspended 
in  Ringer's  solution  the  sarcomata  appeared  as  more  or  less  diffuse 
masses  at  the  site  of  injection,  and  developed  in  a  much  larger  pro- 


TUMORS    OF   A   NATURE    STILL   UNDECIDED 


249 


portion  of  the  inoculated  fowls.  These  observations  led  Rous  and  his 
collaborators  to  assume  that  the  causative  agent  required  for  its  ac- 
tion a  cell  proHferation  or  derangement  such  as  that  induced  by  the 
needle  prick  or  the  presence  of  dried  tissue,  and  experiment  proved 
this  hypothesis  tenable.  A  number  of  susceptible  fowls  having  been 
injected  in  one  breast  with  a  large  quantity  of  active  filtrate  and  in  the 
other  with  an  equal  amount  of  filtrate  to  which  had  been  added  a 
httle  sterile  washed  diatomaceous  earth,  it  was  found  that  in  the  latter 
case  a  larger  number  of  growths  developed  than  where  the  hltrate  had 
been  injected  alone,  and  also,  that  in  the  one  instance  the  tumor  regu- 
larly arose  as  a  diffuse  mass  owing  to  simultaneous  proHferation 
from  many  foci,  whereas  in  the  other  it  slowly  appeared  as  a  small 
discrete  nodule  in  the  needle  track. 

The  importance  of  injury  was  demonstrated  again  in  the  observa- 
tion that  when  large  quantities  of  an  active  Berkefeld  filtrate  free  of 
foreign  particles  were  injected  into  the  circulation,  only  four  tumors 
resulted  among  seventeen  chickens,  while  in  contrast  to  this  propor- 
tion, seven  out  of  twenty  developed  growths  after  a  Httle  diatomaceous 
earth  had  been  added  to  the  filtrate.  Apart  from  these  figures,  how- 
ever, even  the  site  of  those  tumors  arising  after  the  injection  of  filtrate 
free  of  foreign  particles  demonstrated  the  importance  of  ceU  derange- 
ment, for  in  three  cases  the  growth  had  its  primary  seat  in  the  func- 
tioning ovary,  an  organ  where  injury  and  proHferation  are  of  daily 
occurrence,  while  in  the  fourth  the  growth  was  in  a  Hver  where  the 
authors  felt  that  some  focal  derangement  must  have  been  present. 

Significant  though  trauma  might  be,  its  absence  would  not  of  itself 
suffice  to  explain  the  striking  lack  of  infectivity  displayed  by  the  sar- 
coma under  ordinary  circumstances.  Thus,  for  three  years  over  twelve 
hundred  chickens,  many  of  them  bearing  the  sarcoma,  had  been  confined 
at  one  time  or  another  in  relatively  close  quarters.  To  some  of  them 
fresh  sarcomatous  tissue  had  been  fed,  and  many  others  must  have 
been  contaminated  with  the  dried  tumor,  in  which  it  was  known  that 
the  causative  agent  would  remain  alive  for  over  seven  months,  and  yet, 
although  trauma  and  other  types  of  injury  had  been  frequent  among 
the  chickens  so  exposed,  not  one  had  developed  the  sarcoma  except 
after  direct  inoculation.  Furthermore,  the  growth  was  not  naturally 
endemic  among  fowls. 


250  TUMORS    OF    A    NATURE    STILL    UNDECIDED 

The  nature  of  the  other  factors  conditioning  tumor  development 
had  not  yet  been  determined,  but  it  was  e\'ident  that  they  were  both 
local  and  general.  It  was  still  inexpHcable  why,  even  with  the  agent 
in  its  active  form,  and  with  the  factor  of  injury  suppHed,  many  of  the 
fowls  injected  with  a  large  amount  of  filtrate  should  fail  to  develop  a 
growth,  and  why  the  tumors  following  intravenous  injection  were 
seldom  primarily  multiple,  despite  the  numerous  injuries  ever^^vhere 
caused  by  the  infusorial  earth. 

The  conditions  governing  the  appearance  or  non-appearance  of 
growths  possessed  considerable  interest  in  \'iew  of  the  close  resemblance 
of  the  tumor  to  some  malignant  mammalian  neoplasms,  not  only  in 
regard  to  growth  and  general  behavior,  but  also  in  the  obvious  lack  of 
inf ectivity  under  ordinary  circumstances ;  and  that  injury  should  have 
a  share  in  determining  tumor  development  was  noteworthy  in  view 
of  the  importance  of  this  factor  as  a  contributory  cause  of  mammalian 
sarcomata,  including  those  of  man. 

To  determine  whether  pulmonary  metastases  were  invariably  due 
to  the  proliferation  of  transported  cells,  or  whether  they  might  not 
sometimes  follow  localization  of  the  causative  agent  as  such,  a  sus- 
pension of  fresh  tumor  in  Ringer's  solution  was  injected  intravenously. 
It  was  found,  however,  that  secondary  deposits  arose  uniformly  by  a 
sur\dval  and  growth  of  the  inoculated  tumor  cells,  and  this  observa- 
tion, no  less  than  the  one  that  visceral  metastases  occurred  by  far 
most  frequently  in  the  -ungs,  led  to  the  assumption  that  secondary 
nodules  were  a  product  of  the  proliferation  of  cells  sieved  out  of  the 
circulation  by  the  pulmonary  capillaries  in  the  usual  way.  But  to 
explain  the  frequent  involvement  of  the  lungs  there  might  be  enter- 
tained the  alternate  h}q3othesis  that  the  extrinsic  agent,  as  such, 
engendered  tumors  more  easily  in  these  than  in  other  organs.  That 
this  was  not  true,  however,  was  demonstrated  by  the  outcome  of  in- 
travenous injections  of  a  Berkefeld  filtrate  containing  the  causative 
agent,  for  in  only  two  out  of  eleven  fowls  developing  the  growth  after 
such  treatment  was  the  sarcoma  primary  in  the  lungs,  despite  the  fact 
that  the  agent  had  been  directly  carried  there.  In  seven  of  the  cases 
diatomaceous  earth  had  been  added  to  the  filtrate  and  had  lodged  for 
the  most  part  in  the  pulmonary  capillaries,  producing  injuries  such  as 
had  been  found  to  favor  the  action  of  the  agent.     Although  it  was  thus 


TUMORS   OF   A   NATURE    STILL   UNDECIDED  25 1 

certain  that  metastases  were  referable  in  general  to  a  development 
of  cell  emboli,  there  still  remained  the  question  whether  secondary 
tumors  might  not  occasionally  be  caused  by  the  filterable  agent  as 
such,  for  that  this  was  able  to  enter  the  circulation  was  shown  in  some 
instances  by  the  appearance  of  a  sarcoma  after  the  injection  into 
susceptible  hosts  of  large  quantities  of  centrifugalized  plasma  from 
fowls  moribund  with  metastasizing  growths.  The  general  importance 
of  injury  in  determining  the  action  of  the  agent  led  the  authors  to  at- 
tempt the  achievement  of  secondary  tumors  through  trauma,  and  under 
conditions  which  would  show  them  to  be  independent  of  transported 
cells  in  their  origin.  Tissue  derangements  in  tumor-bearing  fowls 
were  produced  by  the  injection  of  Scharlach  R  or  diatomaceous  earth, 
or  by  means  of  incisions  allowed  to  heal  by  secondary  intention,  but 
numerous  experiments  gave  results  almost  entirely  negative,  the  sar- 
coma failing  to  localize  at  the  seat  of  injury.  In  only  a  single  case 
was  there  suggested  the  direct  action  of  the  extrinsic  agent,  where, 
in  a  chicken  bearing  a  very  large  sarcoma,  but  with  no  discoverable 
metastases  in  the  viscera,  a  small  secondary  growth  was  found  post- 
mortem at  the  site  of  injection  of  diatomaceous  earth.  The  heart 
was  not  examined  for  a  patent  foramen  ovale.  Two  other  instances 
of  localization  at  the  point  of  injury  were  less  significant,  since  there 
was  demonstrated  the  presence  of  a  large  number  of  metastases  in  the 
lungs  and  elsewhere.  A  fourth  case  came  to  attention  during  autopsy 
on  a  fowl  with  a  large  inoculated  tumor  and  many  metastases  in  the 
lungs,  the  remainder  of  the  body  having  been  spared  with  the  excep- 
tion of  the  oviduct,  which  contained  an  inspissated  egg  and  exhibited 
a  reactive  thickening  and  increased  vascularization  of  its  walls. 
Whether  in  any  or  all  of  these  tumor-bearing  fowls  the  extrinsic  agent, 
as  such,  had  been  active  in  evolving  a  growth  at  the  site  of  an  injury, 
the  authors  were  unwilling  to  declare. 

The  conditions  governing  the  curious  relationship  between  the 
tumor  and  its  cause  were  of  great  interest.  How  did  it  happen  that 
the  sarcoma,  although  ultimately  dependent  upon  an  extrinsic  agent, 
was  dominated  in  its  behavior  by  the  cells  composing  it  ?  In  answer 
to  this  question  the  author  suggested  several  replies.  The  production 
of  a  neoplastic  change  by  the  causative  factor  might  take  place  with 
such  extreme  slowness,  as  compared  with  the  proliferation  of  cells 


252  TUMORS    OF   A   NATURE    STILL   UNDECIDED 

which  had  once  become  neoplastic,  that  growth  might  seem  to  occur 
entirely  through  the  multiphcation  of  the  cells  in  an  initial  focus. 
Tumors  did  doubtless  result  wholly  in  this  latter  way  in  many  cases, 
because  of  a  second  pecuHarity  of  the  agent  —  its  dependence  on  a 
special  set  of  conditions  in  order  that  it  might  initiate  neoplastic  change. 
The  necessity  for  these  conditions  would  go  far  to  explain  the  failure 
of  the  agent  to  take  an  active  part  in  the  dissemination  of  the  tumor 
throughout  the  body,  granting  that  the  agent  was  present  in  the  cir- 
culation before  the  fowl  was  moribund.  The  possibility  of  the  exist- 
ence of  immune  processes  effective  against  the  agent  when  it  was  sep- 
arated from  the  cells  should  also  be  kept  in  mind,  although  the ' 
evidences  of  resistance  thus  far  recognized  had  been  directed  against 
the  cells  themselves,  as  in  the  case  of  mammalian  tumors. 

Regarding  the  nature  of  the  filterable  agent  causing  the  sarcoma, 
the  most  important  question  for  decision  was  whether  it  was  Uving, 
to  which  the  most  direct  reply  would  be  to  grow  and  transfer  it  in 
culture ;  but  investigation  in  this  direction  had  not  been  particularly 
successful.  Differential  filtration  showed  that  in  a  dilute  tumor  ex- 
tract the  agent  would  pass  through  Berkefeld  filters  which  would 
hold  back  at  the  same  filtration  B.  fluorescens  liquefaciens,  an  organ- 
ism measuring  0.5  micron  by  i.o  to  1.5  micra,  while  on  the  other 
hand,  Chamberland  bougies  (F)  were  impermeable.  Were  it  not 
known  that  filters  of  fine  texture  would  hold  back  complex  proteins 
these  findings  might  indicate  that  the  agent  was  organized,  and  per- 
haps even  visible,  although  repeated  attempts  to  demonstrate  it  with 
special  stains  or  with  the  dark  field  had  been  in  vain. 

The  agent  would  retain  its  activity  in  dried  tissue  for  seven  months, 
and  for  at  least  one  month  in  tissues  placed  in  50%  glycerine,  under- 
going gradual  attenuation,  however,  in  both  instances.  Repeated 
rapid  freezing  and  thawing,  which  reduced  the  tumor  to  a  pulp,  did 
not  greatly  lessen  the  activity  of  the  associated  agent,  although  the 
resistance  of  the  latter  to  heat  was  but  little  greater  than  than  of  the 
neoplasm  itself.  The  sarcoma,  when  submitted  to  a  heat  of  50°  C. 
for  fifteen  minutes,  failed  absolutely  to  grow  in  vitro  where  its  proKf- 
eration  was  ordinarily  very  active,  in  spite  of  the  fact  that  it  often 
gave  rise  to  tumors  when  inoculated  into  susceptible  fowls,  even  after 
exposure  to  53°  C.     Whether  growth  in  vitro  was  a  real  index  of  viabil- 


TUMORS    OF   A   NATURE    STILL   UNDECIDED  253 

ity  was  uncertain,  but  the  ability  of  the  filterable  agent  to  withstand 
a  temperature  of  50°  C.  for  fifteen  minutes  was  demonstrated  a  second 
time  by  the  production  of  tumors  with  tissue  which  had  been  dried, 
ground,  and  heated  after  suspension  in  Ringer's  solution.  Material  that 
had  been  raised  to  a  temperature  of  55°  C.  for  fifteen  minutes,  however, 
never  developed  into  a  tumor.  In  sarcomatous  tissue  autolyzing  at  the 
temperature  of  the  chicken's  body  (41°  C),  the  agent  remained  active 
for  less  than  forty-eight  hours,  while  toluol  and  chloroform  in  the 
proportions  employed  to  prevent  bacterial  growth  during  autolysis 
destroyed  it  in  less  than  two  hours,  as  did  50%  alcohol  or  2%  phenol. 
Unlike  the  virus  of  poKomyeHtis  the  agent  could  not  resist  exposure 
to  0.5%  phenol,  and  like  the  animal  organisms,  in  distinction  to  most 
of  the  vegetable  (v.  Prowacek),  it  was  rapidly  destroyed  by  bile  and  by 
saponin  in  high  dilutions.  Although  no  single  attribute  among  those 
determined  would  suffice  to  show  the  nature  of  the  agent,  its  char- 
acters were  in  general  those  ordinarily  associated  with  micro-organisms. 

It  was  found  that  the  sarcoma  could  be  transplanted  into  the  de- 
veloping embryos  of  barred  Plymouth  Rock  eggs  or  into  the  mem- 
branes, either  by  the  deposition  of  tumor  fragments  or  by  injection 
of  a  cell-free  filtrate.  That  growth  under  these  conditions  was  ex- 
cellent was  shown  by  the  obseryation  that,  in  tumors  of  the  embryo, 
more  cells  on  the  average  were  in  process  of  division  at  one  time  than 
in    those   of    the   adult. 

To  regulate  the  amount  actually  implanted  in  any  tissue  was,  how- 
ever, difficult,  for  that  which  it  was  intended  to  place  in  an  extra- 
embryonic membrane  largely  escaped  at  either  side,  while  that  im- 
planted in  the  embryo  itself  not  infrequently  followed  the  needle  to 
the  surface.  The  majority  of  the  growths  occurred,  in  the  outer 
membrane  (fused  chorion  and  allantois)  for  the  obvious  reason  that 
this  was  necessarily  pierced  in  reaching  other  structures,  so  that  its 
inoculation  could  hardly  be  prevented  during  withdrawal  of  the 
needle.  Tumors  were  discovered  also  in  the  fused  allantoic  and 
amniotic  membranes  and  the  extra-embryonic  body  cavity,  according 
to  the  point  at  which  puncture  had  been  undertaken.  Although  no 
attempt  was  made  to  plant  the  growth  in  special  regions  of  the  embryo, 
since  the  instability  of  the  latter  under  pressure  of  the  needle  rendered 
the  procedure  difficult,  by  indiscriminate  implantations  growths  had 


254  TUMORS    OF    A    XATimE    STILL   tJNDECLDED 

been  obtained  in  the  chest  wah,  heart,  h^^er,  peritoneal  surface  of  the 
gizzard,  and  the  soft  tissue  of  the  thigh  and  of  various  other  parts, 
all  appearing  in  the  track  of  the  needle.  In  the  adult  fowl  it  was  not 
always  necessary  for  the  development  of  tumor  fragments  that  they  be 
brought  directly  into  contact  with  connective  tissue,  since  pieces  intro- 
duced into  the  peritoneal  cavity  might  estabhsh  themselves  despite  the 
endothehal  Hning,  but  it  was  not  so  in  the  extra-embryonic  membranes 
of  the  chick.  Here  a  layer  of  ectoderm  or  endoderm  but  one  cell  thick 
constituted  an  absolute  protection  against  surface  implantation,  and 
only  where  a  mesodermal  layer  was  exposed,  as,  for  example,  on  the. 
outer  side  of  the  allantoic  membrane,  did  such  implantations  occur. 
When  incubation  was  far  advanced  at  the  time  of  inoculation,  and  the 
chick  was  allowed  to  hatch,  tumors  that  had  developed  in  the  outer 
membranes  were  cast  off  \\dth  them.  Growths  in  the  yolk-sac  were 
drawn  with  it  into  the  body  Avhere  they  continued  to  develop.    ■ 

Among  one  hundred  and  forty-seven  inoculated  eggs,  one  or  more 
tumors  resulted  in  one  hundred  and  eight ;  but  of  the  thirty-nine  nega- 
tive attempts,  inoculation  had  been  done  at  a  very  early  period  in 
seventeen,  in  nine  others  a  Berkefeld  filtrate  alone  had  been  intro- 
duced, and  in  five,  dried  material,  leaxdng  but  eight  that  gave  negative 
results  after  the  most  eft'ective  method  of  transplantation,  as  com- 
pared with  one  hundred  and  eight  positive  results  from  inoculations 
of  all  sorts.  Histologically  the  tumors  difi'ered  but  httle  from  those 
in  adult  fowls  ;  although  the  structure  of  the  sarcoma  was  much  looser 
and  the  spindles  might  be  so  attenuated  as  to  suggest  myoma,  necrosis 
was  a  rare  occurrence,  and  infiltration  seldom  well  marked  except 
where  the  growths  lay  in  structures  which,  hke  the  heart  or  liver, 
opposed  a  certain  amount  of  resistance.  Regional  metastases,  pre- 
sumably distributed  by  the  lymphatics,  were  fairly  common  in  the 
outer  allantoid  membrane,  assuming  the  form  of  small  nodules  near 
the  main  growth  and  along  the  larger  vessels  supplying  it.  Remote 
metastases,  however,  had  never  been  encountered,  probably  because 
of  the  structure  of  the  membrane.  By  using  the  outer  allantoid  mem- 
brane as  the  injection  site,  and  emplopng  the  growths  found  there 
after  seven  days,  the  authors  had  succeeded  in  transplanting  the  sar- 
coma to  three  successive  sets  of  eggs,  only  to  lose  it  on  the  fourth 
transfer  by  the  death  of  all  the  embryos.     The  same  event  terminated 


TUMORS    OF   A   NATURE    STILL   UNDECIDED  255 

more  quickly  two  other  series.  During  continued  propagation  in  the 
egg  no  change  was  noted  in  the  behavior  of  the  tumor,  and  inoculation 
back  into  the  adult  yielded  the  characteristic  sarcoma.  While  the 
growth  did  not  proliferate  at  all  in  pigeons  or  ducks,  and  grew  but 
slowly  in  chickens  of  a  variety  other  than  that  in  which  it  originally 
occurred,  with  the  embryos  of  these  alien  fowls  the  results  were  quite 
different ;  thus,  in  four  of  nine  pigeon  eggs  inoculated  and  developing, 
and  in  six  of  sixteen  duck  eggs,  tumors  were  obtained.  Inoculations 
were  made  into  the  membranes  alone,  and  the  resulting  growths  re- 
sembled those  arising  in  similar  situations  in  Plymouth  Rock  eggs, 
which  was  true  also  of  the  tumors  developing  in  the  eggs  of  an  alien 
variety  of  chicken  (Brahma).  When  portions  were  transplanted  to 
adult  pigeons  or  ducks,  implantation  was  always  unsuccessful.  The 
growth  occurring  in  the  eggs  of  pigeons  or  ducks  was  not  analogous 
to  the  brisk  temporary  proliferation  often  seen  in  alien  adults,  be- 
cause there,  even  in  so  short  a  time,  an  immense  accumulation  of 
lymphocytes  took  place  about  the  graft,  which  itself  showed  well 
marked  degenerative  changes.  In  the  embryo,  however,  neither 
phenomenon  was  present. 

Certain  embryos  failed  to  develop  tumors,  a  circumstance  probably 
due  entirely  to  chance  causes  rather  than  to  the  possession  of  natural 
immunity,  for  extensive  search  failed  to  disclose  in  any  instance  those 
histological  signs  about  and  within  the  graft  which  the  authors  were 
accustomed  to  associate  with  the  display  of  resistance  in  the  adult. 

On  the  whole,  young  embryos  (tenth  day  of  incubation)  seemed  to 
offer  a  more  favorable  soil  for  tumor  growth  than  adult  fowls,  and  Rous 
and  his  collaborators  could  see  no  reason  against  extending  this  con- 
clusion to  embryos  at  even  earlier  periods  of  developn.ent,  since  the 
less  striking  results  obtained  before  the  tenth  day  could  be  ascribed 
in  large  part  to  the  method  of  inoculation  and  to  the  relative  unfitness 
of  the  host  to  nourish  the  implanted  tissue,  because  of  small  size  and 
simple  structure. 


CHAPTER  IX 
THERAPEUTICS 

The  discovery  that  cancer  was  not  at  all  of  infrequent  occurrence 
among  animals  and  that  it  could  be  transplanted  from  one  to  the 
other,  placed  within  the  hands  of  the  biologist  a  means  of  investigating 
this  disease  at  once  so  easily  available  and  so  inexhaustible  as  to  en- 
courage the  hope  that  the  scourge  could  not  continue  much  longer  to 
defy  those  who  were  attempting  its  subjugation.  Indeed,  the  con- 
quest of  transplantable  cancer  has  frequently  seemed  an  accomplished 
fact,  but  only  because  it  was  not  fully  appreciated  that  such  tumors 
often  undergo  spontaneous  regression.  Hope  has  run  the  higher,  too, 
since  a  sharp  distinction  has  not  always  been  drawn  between  an 
autochthonous  new  growth  on  the  one  hand,  and,  on  the  other,  a  prop- 
agable  neoplasm  situated  in  alien  soil.  Thus  many  observers  have 
failed  to  reahze  that,  even  though  it  should  prove  possible  to  influence 
detrimentally  the  growth  of  a  transplanted  neoplasm,  there  would  be 
no  reason  to  assume  that  the  curative  agent  would  be  equally  effica- 
cious against  the  proHferation  of  cancer  cells  in  the  organism  to  which 
they  are  native.  However,  investigators  have  begun  to  perceive  the 
distinction,  and  to  appreciate  that  the  cure  of  spontaneous  cancer 
offers  this  therapeutic  puzzle  :  To  find  a  method  of  damaging  a  certain 
area  of  native  cells  while  at  the  same  time  their  neighbors  within  the 
organism  are  left  undisturbed. 

Although  Jensen  ^  at  first  beheved  that  the  serum  of  rabbits  treated 
with  cancer  could  bring  about  the  disappearance  of  transplanted  tumors 
in  mice,  he  -  wrote  later  that  when  he  had  credited  this  serum  with 
curative  power  it  had  not  been  known  that  propagable  tumors  were 
prone  to  retrogress  independently  of  any  treatment  whatsoever.  While 
he  now  reahzed  that  spontaneous  heahng  would  explain  most  of  these 

1  Centralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Orig.,  1903,  xxxiv,  30. 
^  Zeitschrift  f.  Krehsforsch.,  1908-1909,  vii,  281. 
256 


THERAPEUTICS 


257 


earlier  cures,  it  would  not  account  for  the  disappearance  of  several 
very  large  tumors  in  his  series,  and  he  did  not  despair,  therefore,  of  the 
final  discovery  of  a  specific  cytotoxic  serum  against  mouse  cancer. 

V.  Leyden  and  Blumenthal  ^  practised  an  analogous  method  in  dogs, 
successfully  treating  a  cancerous  animal  with  the  serum  of  a  rabbit 
that  had  been  injected  with  dog  cancer.  Another  was  almost  entirely 
cured  of  carcinoma  by  the  inoculation  of  juice  expressed  from  a  dog 
carcinoma.  Furthermore,  alleviation  of  the  disease  in  man  was  said 
to  have  been  brought  about  in  several  instances  after  the  injection 
of  fluids  expressed  from  human  cancer,  a  result  which,  according  to 
V.  Leyden,^  was  confirmed  by  later  investigations. 

Clowes  ^  treated  mice  bearing  propagable  tumors  with  the  serum 
of  mice  in  which  Jensen's  carcinoma  had  been  absorbed,  and  found 
that  while  small  growths  were  restrained  in  development  or  even 
cured,  tumors  of  more  than  three  or  four  grams  in  weight  were  not 
influenced  in  any  way.  Commenting  upon  these  results,  Clowes  * 
said  that  the  inhibitory  effect  could  scarcely  be  interpreted  to  mean 
anything  but  that  the  serum  contained  an  antibody  directly  antag- 
onistic to  the  development  of  neoplastic  cells ;  and  since  it  had  been 
shown  that  the  serum  in  question  possessed  neither  hemolytic  nor 
cytolytic  characteristics,  it  appeared  probable  that  the  effect  was 
exerted  directly  upon  some  intracellular  virus  rather  than  upon  the 
cell  itself. 

Bashford,^  on  the  contrary,  found  that  although  the  action  of  immune 
serum  outside  the  organism  had  in  some  cases  deprived  tumor  cells 
of  their  power  to  grow,  no  definite  evidence  of  such  action  had  been 
obtained  in  the  Uving  body,  while  neither  Borrel  ^  nor  Bridre  ^  was  able 
to  affect  tumors  in  mice  by  injecting  the  animals  with  the  serum  of  sheep 

'  Deut.  med.  Woch.,  1902,  xxviii,  637. 
2  Zeitschrift  f.  Krebsforsch.,  1907,  v,  164. 
^  Johns  Hopkins  Hosp.  Bull.,  1905,  xvi,  130. 

Med.  News,  1905,  Ixxxvi,  477. 

British  Med.  Jour.,   1906,  ii,   1550;   see  also  Gaylord,  Clowes,  and  Baeslack,  Med. 
News,  igos,  Ixxxvi,  91. 

''  British  Med.  Jour.,  1906,  ii,  1552. 
^  British  Med.  Jour.,  1905,  ii,  96. 

Lancet,  1905,  ii,  104. 
^  Bull,  de  Vlnst.  Past.,  1907,  v,  607. 
''  4nn.  de  Vlnst.  Past.,  1907,  xxi,  774. 


258  THER-\PEUTICS 

or  fowls  previously  treated  •u'ith  mouse  cancer.  Furthermore.  Bridre 
could  see  no  conclusive  outcome  from  inoculating  tumor-bearing  mice 
with  fresh  macerated  cancer,  dried  or  heated  tumor  being  even  less 

successful. 

Le\\dn  ^  recorded  the  failure  of  all  attempts  to  obtain  a  curative 
serum  by  the  injection  of  mouse  cancer  into  animals  of  other  species. 
On  the  other  hand,  the  serum  of  rats  in  which  tumors  had  regressed 
spontaneously  produced  a  distinct  retardation  of  the  growth  of  tumors 
in  other  rats,  although  the  cases  were  too  few  to  be  convincing. 

Walker.-  arguing  that  certain  phenomena  proper  to  reproductive 
cells  took  place  also  in  those  of  mahgnant  growths,  and  that  tumor 
cells  seemed  to  be.  hke  reproductive  cells,  out  of  coordination  -uith 
the  rest  of  the  body,  attempted  to  cure  transplanted  carcinomata  in 
mice  by  means  of  the  serum  of  rats  inoculated  with  mouse  testis. 
It  was  found  that  tumors  in  animals  so  treated  grew  with  only  one- 
third  the  rapidit}-  evinced  by  those  in  control  mice  injected  vnth  normal 
rat  serum,  and.  furthermore,  that  favorable  results  could  be  obtained 
also  when  tumor-bearing  mice  were  treated  v^ith  the  serum  of  rats 
inoculated  vvdth  the  same  growth.  The  results  in  all  cases  seemed  to 
be  much  less  satisfactory,'  where  large  tumors  were  treated  than  where 
the  growths  were  small. 

Gay  '^  found  that  when  rats  bearing  the  Flexner-Jobhng  adeno- 
carcinoma were  re-inoculated  with  the  same  growth  not  less  than  three 
or  four  weeks  after  the  primary  implantation,  the  second  graft  failed 
to  grow,  and  in  about  50*^"^  of  the  animals  the  original  tumor  was 
cured  and  metastases  were  prevented. 

Freytag  "*  inoculated  tumor  mice  vdih  the  serum  of  immunized 
rabbits,  with  mouse  blood,  or  with  the  blood  or  serum  of  alien  species. 
Although  regressive  changes  were  evident  within  the  tumors,  complete 
disappearance  had  never  been  observed. 

The    condition    of    parabiosis.'"    introduced    by    Sauerbruch    and 

^  Zeiischrift  f.  Krebsforsch.,  1907-1908,  ^-i,  308. 
^  Laiicet,  1908,  ii,  797,  1299,  1474. 

Lancet,  1910,  i,  990. 

Lancet,  1911,  i,  1275. 

^  Boston  Med.  and  Surg.  Jour.,  1909,  clxi,  211. 
^  Zeitschrift  f.  Krebsforsch.,  1910-1911,  x,  157. 
'  Albrecht  and  Hecht  (Ceniralbl.  f.  allg.  Path.,  etc.,  1909,  xx,  1039)  were  led  to  the  pre- 


THEEAPEUTICS  259 

Heyde/  was  utilized  by  Rous  -  for  the  demonstration  of  the  presence  or 
absence  of  antibodies  in  the  circulation  of  rats  that  had  been  three 
times  unsuccessfully  inoculated  with  the  Flexner-Jobhng  adeno- 
carcinoma. Such  resistant  rats  were  united  in  parabiosis  to  rats  bear- 
ing the  same  tumor,  but  the  union  had  not  the  shghtest  effect  upon  the 
course  of  the  growths,  neither  retarded  development  nor  retrogression 
having  been  observed. 

Uhlenhuth,  Haendel,  and  Steffenhagen  ^  prepared  a  rat  antiserum 
by  injecting  rabbits  with  rat  serum.  Half  a  cubic  centimeter  was  in- 
troduced into  rats  three  times  at  six  day  intervals,  beginning  just  after 
tumor  inoculation,  but  in  spite  of  these  attempts  to  confer  passive 
resistance,  vigorous  tumor  development  took  place.  The  serum^  of  a 
rabbit  that  had  been  injected  intraperitoneally  with  tumor  emulsion 
was  equally  ineffective,  as  were  organ  extracts  and  the  serum  of  cattle. 

Blumenthal  ^  treated  rats  with  autolyzed  transplantable  sarcoma. 
Tumors  the  size  of  a  hen's  egg  were  made  to  disappear  after  one  treat- 
ment, in  spite  of  the  fact  that  nodules  larger  than  a  pigeon's  egg  had 
never  been  known  to  recede  in  untreated  rats. 

Lane-Claypon  and  Starhng  ^  having  postulated  the  existence  of 
hormones,^  or  substances  able  to  stimulate  normal  growth,  A.  and 
H.  Griinbaum  '^  suggested  that,^  given  an  excess  of  a  hormone  together 
Vv^ith  a  lesion  or  irritation  of  the  tissue  complementary  to  the  hormone, 

liminary  conclusion  that  parabiosis  in  animals  otherwise  normal  exerted  a  striking  inhibi- 
tory effect  upon  tiunor  growth  as  well  in  unilateral  as  in  bilateral  inoculation  of  the  para- 
biotic pair.  Such  tumors  as  grew  in  parabiotic  animals  were  retarded  —  a  circumstance 
which  the  authors  considered  analogous  to  immunization  with  blood,  embr>'onal  tissue, 
and  skin.  A  short  time  after  the  separation  of  parabiotic  animals  with  young  tiunors,  a 
distinctly  rapid  and  vigorous  growth  of  the  tiunors  set  in,  which  might  be  explained  by 
the  removal  of  inhibitory  factors. 

Goldmann  {Beitr.  zur  klin.  Chirurgie,  [v.  Bruns],  1911,  Ixxii,  82),  however,  was  imable 
to  convince  himself  that  parabiosis,  as  such,  had  any  inhibitory  effect  upon  tumor  growth. 

1  Milnch.  med.  Woch.,  1908,  Iv,  153. 
Zeitschrift  f.  exp.  Path.  u.  Therap.,  1909,  vi,  33. 

-  Proc.  Soc.  Exp.  Biol,  and  Med.,  1909-1910,  vii,  12. 
Jour.  Exp.  Med.,  1909,  xi,  810. 

'  Arb.  a.  d.  Kaiserl.  Gesundheitsamte,  1911,  xxxvi,  491. 

^  Med.  Klin.,  1910,  vi,  1982. 

^  Proc.  Roy.  Soc.,  Series  B.,  1906,  Ixxvii,  505  ;  see  also  Starling,  Lancet,  1905,  ii,  579. 

^  For  a  refutation  of  Starling  and  Lane-Claypon's  results,  however,  see  Frank  and 
Unger,  Arch.  Internal  Med.,  1911,  vii,  812. 

''Jour.  Path,  and  Bad.,  1911,  xv,  289. 


26o  THERAPEUTICS 

unlimited  growth  might  take  place.  When  immune  rats  were  inocu- 
lated with  rat  sarcoma  and  parotid  gland  together,  the  result  indicated 
that  the  gland  was  able  to  assist  the  growth  of  sarcoma  in  animals 
otherwise  insusceptible,  while,  on  the  other  hand,  removal  of  the  parotid 
gland  from  a  tumor-bearing  rat  was  followed  by  the  occurrence  within 
the  nodule  of  fatty  and  fibrotic  changes,  although  growth  continued 
progressively.  Other  experiments  with  the  parotid  gland,  or  the 
ovary,  were  indecisive. 

The  same  authors  ^  found  it  possible  to  effect  the  regression  of  small 
transplanted  rat  tumors  by  injecting  antivenom  horse  serum,  and 
found  further  ^  that  by  the  simultaneous  administration  of  adrenalin 
they  could  bring  about  the  disappearance  of  still  larger  growths  in 
about  70%  of  the  animals  inoculated. 

Beard  ^  recorded  the  successful  treatment  of  Jensen's  mouse  tumor 
with  trypsin,  and  ascribed  it  to  destruction  of  the  less  powerful  fer- 
ment of  the  cancer,  malignin,  by  the  more  active  trypsin. 

Vidal  ^  had  observed  the  arrested  evolution  of  tumors  in  four  pa- 
tients with  a  temperature  above  40°  C.  In  order  to  be  sure  that  this 
was  not  a  quadruple  coincidence  Vidal  daily  exposed  tumor-bearing 
mice  to  a  temperature  above  that  of  the  normal  organism,  and  found 
that  they  Hved  longer  than  their  controls  and  that  their  tumors  were 
the  seat  of  degenerative  changes.  In  a  bitch  the  subject  of  spontan- 
eous lympho-sarcoma  the  "zone  of  Richet"  was  punctured,  in  con- 
sequence of  which  the  temperature  rose  to  40.8°  C,  while  the  tumor 
diminished  rapidly  in  size,  finally  to  disappear. 

The  action  of  X-rays  upon  the  new  growths  of  animals  has  been  in- 
vestigated by  several  observers.  Clunet  ^  found  sHght  hyperplasia  and 
accentuation  of  the  cystic  structure  in  transplantable  and  spontaneous 
carcinomata  of  mice  exposed  to  these  rays,  and  discovered  at  a  later 
period  still  more  serious  lesions  which  were  coincident  with  macro- 
scopic alterations.  Marie  and  Clunet,^  in  summing  up  the  changes 
which  they  had  observed  both  in  human  carcinomata  and  in  those  of 

1  Lancet,  191 1,  i,  879. 

2  Lancet,  1912,  i,  644. 

3  British  Med.  Jour.,  1906,  i,  140. 

'^  Travaux  de  la  deuxieme  Conference  internal,  pour  l' Etude  du  Cancer,  Paris,  191 1,  302. 

5  Recherches  exp.  sur  les  Tumeurs  malignes,  Paris,  1910,  250. 

6  Travaux  de  la  deuxieme  Conference  internal,  pour  V Etude  du  Cancer,  Paris,  191 1,  160. 


THER.\PEUTICS  26 1 

the  mouse,  described  a  latent  stage  signalized  by  the  occurrence  of 
a  large  number  of  abnormal  cells  and  followed  by  one  of  ceU  death. 
In  the  third  stage  groups  of  necrotic  cells  were  replaced  by  poly- 
morphonuclear leucocytes  and  young  connective  tissue,  while  in  the 
fourth  there  occurred  the  formation  of  a  scar,  which  for  a  long  time 
inclosed  in  its  meshes  cells  of  ''diminished  \dtality." 

Contamin  ^  found  that  the  younger  the  growth  the  more  readily 
could  it  be  brought  to  absorption  "^nth  X-rays,  and  that  irradiation 
before  inoculation  exerted  a  direct  action  upon  maHgnant  cells,  affect- 
ing more  their  growth  energy  than  their  ability  to  A^ithstand  trans- 
plantation. 

As  for  the  effect  of  radium.  Apolant  -  reported  that  manv  mice 
bearing  transplantable  carcinomata  had  been  entirely  cured,  while 
in  the  remainder  the  tumors  had  been  very  materially  reduced  in  size. 
During  the  earher  periods  of  healing  there  were  to  be  found  in  the  con- 
nective tissue  a  series  of  changes  presenting  all  the  signs  of  inflamma- 
tion, among  which  the  presence  of  large  iibroblasts  was  especially 
noticeable.  These  ceUs  penetrated  the  tissues  in  all  directions,  and 
w^andering  cells  continued  to  the  interior  of  the  alveoli  instead  of  halt- 
ing at  the  edges ;  the  alveoH  themselves  were  continually  under  sub- 
division by  advancing  fibroblasts,  and  the  epithehal  cells  within  them 
lost  their  sharp  contours  in  the  process  and  came  to  resemble  a  syn- 
cytium. The  changes  were  essentially  similar  to  those  described  in 
man,  in  that  there  was  a  disappearance  of  epithehal  elements  and  an 
overgrowth  of  connective  tissue.  In  Apolant's  opinion  it  was  hardly 
to  be  doubted  that  radium  possessed  a  specific  action  upon  the  malig- 
nant cells  because  these  elements  were  entirely  absorbed  under  its 
influence,  while  those  in  a  tumor  undergoing  spontaneous  regression 
were,  on  the  contrary,  transformed  into  necrotic  masses  which  never 
underwent  absorption. 

Bashiord,  ^Murray,  and  Cramer  ^  also  described  the  spHtting  up  of 
alveoH  into  smaller  cell  groups  by  proHferating  connective  tissue, 
but  denied  that  radium  had  any  selective  action  upon  tumor  cells. 
On  the  contrary,  when  the  connective  tissue  proHferation  was  at  its 

^  Bull,  de  r Assoc,  franq.  pour  VEtude  du  Cancer,  1910,  iii,  160. 

^  Deut.  med.  Woch.,  1904,  .x.xx,  454,  11 26. 

^.Sci.  Reports,  Imperial  Cancer  Research  Fund,  London,  1905,  Xo.  2,  Part  ii,  56. 


262  THERAPEUTICS 

height  tumor  cells  could  be  found  in  active  division  and,  furthermore, 
tumors  could  be  successfully  transplanted  even  after  a  prolonged 
exposure  to  radium.  As  great  engorgement  of  the  blood  vessels,  and 
even  hemorrhage,  were  prominent  features  in  growths  that  had  been 
treated,  the  attempt  was  made  by  these  authors  to  produce  bleeding 
by  other  agencies  in  order  to  determine  its  significance  in  the  earlier 
stages  of  the  radium  reaction.  For  this  purpose  mice  with  gromng 
tumors  were  injected  with  one  cubic  centimeter  of  a  one  to  ten  thousand 
solution  of  adrenaHn  in  the  hope  that  the  great  rise  in  blood  pressure 
would  cause  an  extravasation  of  blood  from  the  capillaries  of  the  tumor, 
since  they  possessed  neither  vasomotor  nerves  nor  the  muscular 
mechanism  by  which  these  act.  Mice  dying  within  the  first  twelve 
hours  after  injection  showed  widespread  hemorrhages  into  the  lung 
and  into  the  substance  of  the  tumor.  Three  animals  sur\dved  these 
large  doses  of  adrenahn,  and  in  one  of  them  the  growth,  which  by  the 
fifth  day  had  diminished  in  size,  presented  the  same  histological  ap- 
pearance as  resulted  from  the  action  of  radium. 

Reicher  ^  reported  that  he  had  succeeded  in  curing  transplantable 
sarcomata  and  carcinomata  in  rats  and  mice  through  injection  of 
adrenahn  into  the  tissues  surrounding  the  growths.  Microscopic  ex- 
amination showed  a  central  necrosis  surrounded  by  a  secondary  in- 
flammatory reaction. 

Spiess,-  in  continuation  of  his  previous  investigations  upon  the  effect 
of  anesthesia  on  inflammation,  injected  anesthetics  into  the  sarcomata 
or  carcinomata  of  mice,  employing  for  the  purpose  nirvanin,  novo- 
caine,  and  a  third  substance  ("337  ")  not  upon  the  market.  In  a  pre- 
liminary experiment  the  last-named  proved  to  be  the  most  active,  and 
the  other  two  were  accordingly  discarded.  Seventy-eight  mice  in  all 
were  treated  ^^ith  "337,"  their  tumors  varpng  from  the  size  of  a  pea 
to  that  of  a  hazel-nut,  and  of  the  seventy-four  appearing  in  the  final 
reckoning,  fifty-two  were  favorably  influenced ;  of  these,  twenty-two 
were  entirely  cured,  sixteen  showed  great,  and  fourteen  less,  though 
still  distinct,  improvement.  The  more  mahgnant  were  the  tumors, 
the  less  favorable  was  the  outcome,  and  only  tumors  of  slowly  growing 
strains  could  be  cured.     That  spontaneous  healing  need  not  be  taken 

1  Deut.  med.  Woch.,  1910,  xxxvi,  1356. 
^  Zeitschrift  f.  Krehsforsch.,  1907,  v,  81. 


THERAPEUTICS  263 

into  account  was  shown  by  the  different  course  of  events  in  treated 
mice,  by  the  observation  that  control  tumors  grew  rapidly  and  led  to 
the  death  of  the  animals  bearing  them,  and  finally,  by  the  fact  that 
animals  which  had  been  cured  were  not  refractory  to  re-inoculation. 

Uhlenhuth  and  Weidanz/  investigating  the  action  of  atoxyl  on  mouse 
tumors,  found  that  growth  was  so  much  more  rapid  in  treated  animals 
than  in  their  controls  that  after  a  month's  medication  the  tumors  were 
nearly  twice  as  large.  Pyocyanase,  on  the  contrary,  when  injected 
directly  into  rat  sarcomata,  brought  about  the  disappearance  of  tumors 
even  after  they  had  attained  the  size  of  a  walnut. 

Uhlenhuth,  Haendel,  and  Steff enhagen  -  employed  quinine,  sodium 
taurocholate,  ox-gall,  antiformin,  arsenophenylglycin,  ferments,  ad- 
renalin, alcohol,  and  the  appHcation  of  cold.  None  of  these  was  so 
effective  as  pyocyanase  which,  however,  was  found  to  be  poorly  borne 
by  rats. 

Beck^  investigated  the  action  of  arsenic,  atoxyl  or  some  of  its  prep- 
arations, and  quinine,  finding  them  all  without  effect.  More  favorable 
results  followed  the  use  of  certain  substances  prepared  from  bacteria 
or  their  metabohc  products  (if  injections  were  made  directly  into  the 
tumor),  and  filtrates  and  extracts  from  B.  prodigiosus  and  5.  pyogenes 
aureus  were  employed  w4th  success  although  other  bacterial  prepara- 
tions, as  tuberculin,  were  without  curative  action. 

V.  Wassermann,  Keysser,  and  Wassermann  ^  outhned  the  difficulty 
of  attacking  the  mahgnant  cell  somewhat  as  follows,  employing  the 
terminology  of  Ehrlich.  While  in  treating  the  protozoal  diseases  the 
aim  of  the  investigator  was  to  prepare  a  medicament  which  would 
be  parasitotropic  but  not  organotropic,  the  problem  in  cancer  was  to 
obtain  a  material  which  should  be  organotropic,  but  whose  action 
should  be  Hmited  to  a  certain  area  in  the  organ  —  the  tumor  cells. 

To  affect  the  very  mahgnant  neoplasms  of  the  mouse  it  would  be 
necessary  either  to  employ  an  unusually  powerful  agent  or  to  find 
a  means  of  attacking  the  nucleus,  the  most  vital  point  of  the  tumor 
cell ;  it  would  be  necessary,  in  other  words,  to  discover  a  nucleotropic 

1  Arb.  a.  d.  Kaiserl.  Gesundheitsamte,  1909,  xxx,  444. 

2  Centralbl.  f.  Bakt.,  etc.,  erste  Abt.,  Ref.,  1910,  xlvii,  Beiheft,  159. 
Arb.  a.  d.  Kaiserl.  Gesimdheitsamte,  1911,  xxxvi,  492. 

^  Zeitschrift  f.  Krebsforsch.,  1910-1911,  x,  153. 
*  Deut.  med.  Woch.,  1911,  xxxvii,  2389. 


264  THERAPEUTICS 

substance.  This  would  have  to  be  at  the  same  time  a  material 
capable  of  exerting  its  curative  effect  when  introduced  by  way  of  the 
blood  stream,  for  all  agents,  when  locally  employed,  lacked  the  neces- 
sary elective  power  to  make  their  own  way  to  the  neoplastic  cell. 
Gosio  ^  had  discovered  that  tellurium  and  selenium  were  reduced  by 
living  bacteria  as  black  and  red  precipitates  respectively,  and  the  pres- 
ent authors  found  that  in  the  case  of  the  cancer  cell  this  reduction, 
in  vitro  at  least,  was  most  intense  about  the  nuclei.  It  was  then  es- 
sential to  know  whether  the  specific  reaction  would  occur  in  the  living 
organism.  While  preparations  of  selenium  or  tellurium,  injected 
into  a  tumor,  were  found  to  have  a  destructive  effect  upon  its  cells, 
this  was  especially  true  of  tellurium.  But  as  these  compounds  re- 
mained entirely  inert  after  introduction  into  the  body  through  the 
blood  stream  because  they  had  not  succeeded  in  reaching  the  malig- 
nant growth,  it  was  necessary,  in  the  words  of  the  authors,  to  con- 
struct a  railway  by  means  of  which  the  selenium  and  tellurium  could 
be  carried  to  their  destination.  Because  in  mouse  tumors  the  blood 
supply  was  Hmited  almost  entirely  to  the  periphery,  it  was  necessary 
to  use  for  this  purpose  a  rapidly  diffusible  substance,  and  after  many 
trials  it  was  found  that  eosin  fulfilled  the  requirements.  This  dye, 
combined  with  selenium  and  injected  into  the  circulation  of  mice 
bearing  transplantable  growths,  produced  an  immediate  reddening  of 
the  entire  animal,  although  no  effect  upon  the  tumor  was  noticeable 
until  three  daily  inoculations  had  been  given.  After  the  third  treat- 
ment a  distinct  softening  was  demonstrable,  while  after  the  fourth  the 
tumor  felt  more  like  a  fluctuating  cyst  than  a  sohd  nodule ;  and  after 
this  condition  had  been  obtained  absorption  set  in  until,  within  ten 
days,  the  cure  was  complete.  Often,  however,  recovery  was  not  so 
uneventful  and,  as  was  especially  the  case  with  large  tumors,  the  mice 
were  killed  by  a. toxemia  resulting  from  the  absorption  of  their  own 
growths.  Two  mice  with  spontaneous  tumors  had  also  been  cured, 
and  four  strains  of  transplantable  carcinoma  and  one  propagable 
sarcoma  had  all  proved  equally  susceptible  to  treatment.  Tumors  in 
control  mice,  on  the  contrary,  continued  to  grow  progressively.  Re- 
covered animals  had  been  kept  under  observation  for  months,  but  no 
suggestion  of  recurrence  had  been  observed.     In  mice  autopsied  dur- 

1  Zeitschrift  f.  Hyg.,  etc.,  1905,  li,  65. 


THERAPEUTICS  265 

ing  the  first  few  days  of  treatment  the  growths  were  stained  an  intense 
red  as  contrasted  with  the  surrounding  tissues,  showing  that  the  neo- 
plastic cells  had  exerted  a  specific  attraction  upon  the  injected  material. 
As  the  eosin-selenium  compound  was  extremely  toxic,  and  as  it  was  un- 
fortunately necessary  to  give  almost  the  lethal  dose  in  order  to  achieve 
a  cure,  many  mice  perished  merely  as  the  result  of  the  injection. 

V.  Hansemann,^  in  conjunction  with  the  three  authors  previously 
mentioned,  discussed  the  histological  appearance  of  treated  tumors, 
and  found  evidence  to  support  the  selective  action  of  selenium  upon 
the  nuclei.  Examinations  of  the  organs  of  injected  mice  showed  no 
serious  lesion  attributable  to  the  treatment. 

All  four  investigators  united  in  declaring  that  the  treatment  was 
still  in  the  experimental  stage,  and  that  it  marked  rather  the  intro- 
duction of  a  new  era  of  chemotherapy  than  the  discovery  of  a  cure  for 
cancer. 

In  discussing  the  work  of  v.  Wassermann  and  his  collaborators 
Klemperer  ^  said  that  he  also,  in  conjunction  with  Emil  Fischer,  had 
been  able  to  cause  the  regression  of  mouse  tumors  with  selenium. 

Walker  ^  began  a  series  of  experiments  with  selenium  immediately 
after  the  publication  of  v.  Wassermann's  article.  The  first  preparation 
to  be  investigated  was  a  combination  of  colloidal  selenium  and  eosin, 
but  this  proved  to  be  entirely  Vithout  effect  upon  the  transplantable* 
tumors  of  rats  and  mice.  It  was,  however,  non-toxic,  in  contrast 
to  the  highly  poisonous  preparation  of  the  German  investigator. 
Combinations  of  selenium  and  eosin  of  doubtful  composition  were 
also  tried,  but  although  they  were  highly  poisonous  none  of  them 
showed  the  slightest  selective  action  upon  tumor  cells. 

Neuberg  and  Caspari,^  starting  with  the  observations  that  tumors 
were  characterized  by  increased  fermentive  activity,  particularly 
autolysis  (in  the  widest  sense  of  the  word),  and  that  certain  substances 
like  radium  and  compounds  of  the  heavy  metals  in  colloid  form  were 
capable  of  increasing  autolysis  in  vitro,  tried  to  influence  tumor  growth 
by  intravenous  injections  of  compounds  of  the  heavy  metals.  They 
were  able  to  find  several  materials  possessed  of  an  affinity  for  malignant 
cells  —  compounds  of   gold,   platinum,    silver,   rhodium,   ruthenium, 

^  Berl.  klin.  Woch.,  191 2,  xlix,  4.  ^  Deiot.  med.  Woch.,  191 2,  xxxviii,  89. 

^Lancet,  1912,  i,  1337.  * Deut.  med.  Woch.,  1912,  xxxviii,  375. 


266  THERAPEUTICS 

iridium,  lead,  and  especially  copper  and  tin.  Other  substances, 
arsenic  and  vanadium,  also  exerted  an  action  upon  autolysis,  although 
a  less  certain  one.  Sulphur,  and  iodine  and  its  compounds  were,  on 
the  contrary,  entirely  inert.  In  a  later  article  Neuberg,  Caspari,  and 
Lohe  ^  added  compounds  of  antimony,  mercury,  cobalt,  osmium,  and 
palladium  to  the  list  of  active  materials.  Microscopic  deposits  of  the 
metals  employed  were  to  be  found  in  the  tumors  cf  animals  that  had 
been  subjected  to  treatment. 

The  attack  of  these  elements  was  extraordinarily  sudden,  beginning, 
sometimes  after  as  short  an  interval  as  one  minute,  with  extreme  con- 
gestion, which  was  shortly  followed  by  the  hemorrhage  initiating  the  ■ 
cure.  Within  the  first  twenty-four  hours  a  tumor  of  considerable 
size  might  become  almost  entirely  softened,  while  repeated  injections 
resulted  in  an  entire  liquefaction  and  absorption  of  the  nodule. 
Several  strains  of  transplanted  tumors,  as  well  as  sporadic  growths, 
proved  equally  amenable  to  treatment,  and  as  spontaneous  recoveries 
from  the  transmissible  growths  employed  were  very  rarely  encoun- 
tered, the  authors  rejected  the  possibility  that  healing  might  not  have 
been  the  result  of  their  treatment.  The  materials  used  were  all  toxic 
and,  as  in  v.  Wassermann's  experiments,  the  effective  dose  lay  very 
near  the  lethal  amount,  wherefore  these  observers  were  unwilling  to 
forecast  the  relation  of  their  investigations  to  the  treatment  of  cancer 
in  the  human  subject. 

The  question  of  chemotropism  in  neoplastic  tissue  has  been  re- 
viewed by  von  den  Velden.^  Simple  though  the  conception  might 
be  that  one  material  could  act  as  a  pilot  or  a  railway  to  direct  or  trans- 
fer another  substance  to  its  destination,  the  discovery  of  such  a  com- 
bination was  an  entirely  different  matter.  The  union  must  not  be  so 
unstable  as  to  be  broken  down  in  the  stomach,  the  tissues,  or  the  blood, 
nor  yet  so  firm  that  the  active  principle  could  be  deterred  from  exert- 
ing its  effect  through  remaining  coupled  after  arrival  at  its  goal.  The 
clearest  instance  of  specific  affinity  was  offered  by  iodine,  and  was  best 
expressed  negatively  by  saying  that  fat,  as  well  as  the  central  nervous 
system  with  its  large  lipoid  content,  was  practically  barren  of  iodine. 
Oswald  Loeb  had  shown,  nevertheless,  that  iodine  could  be  made  to 
penetrate  both  fat  and  the  central  nervous  system  if  it  were  first  com- 

1  Berl.  Mill.  Woch.,  1912,  xlix,  1405.  2  ^^j-i  j^n^^^  Woch.,  1912,  xlix,  825. 


THERAPEUTICS  267 

bined  with  a  lipoid.  Thus  was  afforded  an  example  of  an  exogenous 
factor  with  power  to  alter  the  distribution  of  a  chemical  substance 
within  the  body.  Contrasted  with  this  instance  there  were  certain 
endogeneous  factors.  A  change  in  the  relative  bulk  of  the  various 
tissues  might  act  in  this  way,  as  was  demonstrated  by  the  difference  in 
what  occurred  when  a  material  soluble  in  lipoids  was  administered  to  a 
very  thin  or  a  very  fat  person.  The  endogenous  factors  were  most 
distinct,  however,  under  pathological  conditions,  as  Jacoby  had  shown 
by  his  work  on  saHcylic  acid.  Thus,  in  a  rabbit  with  experimentally 
produced  general  sepsis,  sahcyHc  acid  would  be  taken  up  in  large 
amounts  by  the  joints  although  previously  they  held  none  of  this 
drug ;  furthermore,  Oswald  Loeb  and  Michaud  had  shown  that  in 
turpentine  abscesses  and  in  the  tuberculous  eyes,  lymph  nodes,  and 
lungs  of  guinea-pigs  and  rabbits,  there  occurred  a  very  appreciable 
storing  of  iodine  when  potassium  iodide  had  been  introduced  into  the 
body,  von  den  Velden  himself  had  been  able  clearly  to  demonstrate 
iodine  in  metastatic  carcinomata  of  the  liver  and  pancreas  after  intro- 
ducing into  a  moribund  cancer  patient  one  gram  of  sodium  iodide  for 
every  twenty  kilograms  of  body  weight,  although  the  tissues  them- 
selves in  which  the  secondary  nodules  were  embedded  contained  no 
iodine.  This  finding  had,  furthermore,  been  confirmed  by  Takemura, 
who  found  that  mouse  carcinobiata  and  rat  sarcomata  were  capable 
of  storing  up  iodine,  while  Blumenthal  had  discovered  a  tropism  for 
neoplastic  tissues  in  the  case  of  arsenic. 

The  affinity  of  various  chemicals  for  certain  organs  had  been  re- 
ferred by  Oswald  to  changes  in  the  diffusion  processes  caused  by  altera- 
tions in  the  colloid  structure  of  the  membrane  and  peripheral  portions 
of  the  cells  ;  and  as,  in  the  opinion  of  that  author,  similar  alterations 
were  to  be  found  not  only  in  inflammatory  processes  but  in  new 
growths  as  well,  the  "membrane  problem"  thus  suggested  became  of 
such  wide  significance  that  it  might  transfer  the  entire  field  of  in- 
vestigation to  the  realm  of  physical  chemistry. 

Therapeutic  experiments  have  been  undertaken  not  infrequently 
in  man  also,  certain  of  them  inspired  without  doubt  by  the  early 
endeavors  of  Hericourt  and  Richet  ^  to  obtain  an  immune  serum  from 

1  Compt.  rend,  de  I' Acad,  des  Sc,  1895,  cxx,  948. 
Compt.  rend,  de  VAcad.  des  Sc,  1895,  cxxi,  567. 


268  THERAPEUTICS 

animals  injected  with  human  cancer,  although  others,  falling  within 
the  domain  of  immunity,  have  been  attempts  to  transfer  to  man  such 
knowledge  as  has  been  gathered  by  observation  upon  the  lower  ani- 
mals. The  investigations  which  have  been  prosecuted  in  the  labora- 
tory within  the  last  decennium  have,  however,  yielded  no  result  ger- 
mane to  therapeutics  other  than  to  show  that  an  animal  can  be  made 
resistant  to  the  transplantation  of  malignant  cells  from  another  or- 
ganism, and  the  fallacy  of  appl^dng  these  findings  to  the  treatment 
of  tumors  autochthonous  in  origin  and  firmly  estabHshed,  has  been  in- 
dicated by  Bashford  ^  as  follows,  in  a  discussion  of  the  refractory  con- 
dition in  animals:  "It  is  necessary  to  point  out  emphatically,  that- 
nothing  but  harm  can  result  from  ignoring  the  fact  that  the  above 
experiments  only  indicate  the  possibility  of  rendering  normal  mice 
unsuitable  for  the  growth  of  experimental  cancer.  They  have  not 
enabled  us  to  arrest  the  progress  of  experimental  tumours  with  cer- 
tainty, far  less  to  affect  the  cure  of  the  disease  occurring  naturally." 

Fichera  ^  attempted  to  cure  cancer  in  rats  and  in  the  human  subject 
by  injecting  autolyzed  rat  embryo  in  the  one  case,  and  autolyzed  hu- 
man embryo  in  the  other.  Twenty-five  patients  with  tumors  of  various 
kinds  continued  treatment  long  enough  to  allow  the  method  a  fair 
trial.  While  nine  of  them  showed  no  improvement  whatever,  in  the 
remainder  there  occurred  arrest  of  development,  involution,  or  some- 
times temporary  disappearance  of  the  growth. 

Coca  and  Oilman  ^  injected  a  series  of  patients,  each  with  his  own 
carcinoma  after  it  had  been  thoroughly  ground  and  emulsified,  and 
found  the  results  encouraging.  A  footnote  stated  that  a  carcinoma 
of  the  same  kind  taken  from  another  individual  might  be  substituted. 

In  a  later  article,  however.  Coca,  Dorrance,  and  Lebredo  ^  concluded 
from  a  study  of  seventy-nine  cases  that,  except  for  the  rapid  relief 
of  cachectic  symptoms,  they  had  seen  no  evidence  that  the  injection  of 
tumor  tissue  exerted  any  specific  influence  over  malignant  growths. 

Rovsing,^  who  introduced  heated  tumor  emulsions,  gained  the  im- 

^  British  Med.  Jour.,  1906,  ii,  209. 

^  Tumori,  Turin,  1911 ;  abstr.  in  Bull,  de  Vlnst.  Past.,  1911,  ix,  272  ;  see  also  Lancet, 
1911,  ii,  1194. 

^Philippine  Jour.  Sci.,  1909,  iv,  B,  391. 

*  Zeitschrift  f.  Imniunitdtsforsch.,  etc.,  Orig.,  1912,  xiii,  543. 

*  Travaux  de  la  deuxieme  Conference  internal,  pour  I'Etude  du  Cancer,  Paris,  1911,  562. 


THERAPEUTICS  269 

pression  that  although  this  treatment  was  without  effect  upon  car- 
cinomata  it  might  possibly  prove  valuable  against  sarcomata. 

Hodenpyl  ^  offered  a  preliminary  report  regarding  the  treatment  of 
cancer  by  means  of  ascitic  fluid  withdrawn  from  a  patient  in  whom 
both  primary  and  recurrent  carcinomata  had  disappeared.  The  fluid 
was  tested  first  upon  mice  bearing  transplantable  carcinomata,  and 
when  it  had  been  found  that  these  growths  diminished  in  size  or  even 
disappeared,  the  experiment  was  extended  to  include  forty-seven  in- 
operable cases  in  man.  In  general  the  effect  of  the  injection  was  to 
cause  a  temporary  redness,  tenderness,  and  swelling  in  the  neighbor- 
hood of  the  growth,  this  reaction  being  followed  by  necrosis  of  the 
tumor  and  a  decrease  in  size  or,  in  some  instances,  by  complete 
disappearance. 

Ill  and  Miningham  ^  obtained  ascitic  fluid  from  a  somewhat  similar 
case  and  introduced  it  into  more  than  thirty  patients  with  malignant 
disease.  Although  not  a  single  case  was  cured,  pain  was  mitigated, 
hemorrhage  was  decreased  or  entirely  stopped,  and  there  occurred  a 
transient  gain  in  weight.  The  psychic  element  was  eliminated  from 
this  striking  improvement  in  the  general  condition  by  the  fact  that 
only  one  patient  knew  the  nature  of  her  disorder. 

A  useful  resume  of  the  serum  therapy  of  cancer,  which  contains 
nearly  one  hundred  and  fifty  references,  has  been  compiled  by  Vidal,^ 
while  Coca  ^  has  but  recently  prepared  a  critical  review  of  the 
''vaccination"  treatment  for  human  cancer  in  its  relation  to  the  ex- 
perimental data  bearing  upon  normal  tissue  and  tumor  immunity. 

^  Med.  Record,  1910,  Ixxvii,  359. 

^  Jour.  American  Med.  Assoc,  191 2,  lix,  497. 

*  Travaux  de  la  deuxieme  Conference  internal,  pour  V Etude  du  Cancer,  Paris,  191 1,  293. 

^  Zeitschriftf.  Immunitdtsforsck.,  etc.,  Orig.,  1912,  xiii,  524. 


CHAPTER  X 
GENERAL  SUMMARY 

Although  the  literature  of  experimental  cancer  may  seem  to  be 
a  maze  of  conflicting  statements,  there  are  nevertheless  a  few  threads 
which  may  be  fixed  upon  and  followed  through.  These  are  repre- 
sented by  a  number  of  findings  which,  ha^'ing  received  the  support 
of  a  majority  of  those  engaged  in  cancer  research,  may  be  accepted 
as  probably  rehable.  Nevertheless,  it  has  happened  occasionally  that 
even  the  most  competent  observ^ers  have  come  to  diametrically  opposed 
conclusions  in  spite  of  the  most  careful  work,  a  situation  suggesting 
that  differences  still  unrecognized  may  have  existed  between  the 
animals  used  in  the  several  experiments.  The  mouse  is  not  a  test 
tube  where  so  much  of  one  substance  and  so  much  of  another  will 
alv/ays  produce  so  much  of  a  third,  but  is,  on  the  contrary,  a  highly 
complex  organism  exhibiting  protean  reactions.  \\Tiat  takes  place, 
therefore,  in  one  mouse  may  not  happen  in  the  next  —  nay,  what 
happens  in  two  groups  of  ten  mice  each  may  not,  and  often  does  not, 
occur  in  a  third  series. 

Malignant  growths  have  been  found  throughout  the  animal  kingdom 
down  to,  and  including,  the  fish  —  except  that  no  certain  instance  has 
yet  been  reported  among  the  reptiles.  By  far  the  greater  amount  of 
attention  has,  however,  been  bestowed  upon  the  disease  in  the  mouse, 
not  only  on  account  of  the  ease  with  which  this  animal  can  be  procured 
and  the  cheapness  and  facihty  with  which  it  can  be  kept  under  ob- 
servation, but  also  because  the  subcutaneous  situation  of  its  tumors 
makes  for  early  and  ready  recognition.  The  fact  that  information 
has  been  accumulating  chiefly  in  regard  to  mouse  cancer  must  not, 
therefore,  be  understood  to  imply  that  the  findings  might  not  hold 
good  for  malignant  new  growths  of  other  species,  were  it  convenient 
or  possible  to  investigate  them  in  the  same  way.  There  can  be  scarcely 
a  doubt  that  the  neoplasms  of  the  mouse  are  entirely  comparable  to 

270 


GENERAL   SUMMARY 


271 


those  of  man,  since  they  exhibit  continuous,  infiltrative,  growth,  no 
less  than  the  power  to  metastasize  and  to  recur  after  incomplete  re- 
moval. 

Evidence  has  been  adduced  that  there  is  some  hereditary  influence 
at  work,  making  mice  of  recently  cancerous  ancestry  more  prone  to 
develop  cancer  than  are  those  in  which  the  taint  is  more  remote.  But 
whether  or  not  this  observation  may  be  appHed  to  man  it  is  at  present 
impossible  to  determine,  nor  would  it  be  safe  to  venture  an  opinion 
until  data  as  accurate  as  those  relating  to  the  mouse  become  available. 

It  has  been  ascertained  that  almost  any  spontaneous  new  growth  of 
the  mouse  can  be  transplanted  into  other  mice,  and  that  although  the 
first  inoculation  may  not  be  attended  by  any  great  degree  of  success, 
propagation  generally  becomes  easier  in  succeeding  generations.  Why 
this  should  be  so  is  not  known ;  some  observers  ascribe  it  to  an  in- 
crease of  virulence  on  the  part  of  the  tumor  cell,  while  others  see  in  it 
merely  an  increasing  power  of  this  element  to  adapt  itself  to  altered  con- 
ditions. It  has  been  the  experience  of  the  majority  of  investigators 
that  for  transmission  to  be  eft'ective,  living  and  intact  cells  must  be 
introduced  into  an  animal  of  the  same  species  as  that  in  which  the 
primary  tumor  took  its  origin,  or  at  least  into  a  species  very  closely 
related. 

In  this  connection  there  has  been  discovered  a  phenomenon  of  the 
highest  importance.  It  is  that  cancer  is  more  readily  transplantable 
into  the  animal  in  which  it  arose  spontaneously  than  into  any  other^ 
This,  and  the  complementary  observation^  that  an  animal  cannot  be 
immunized  in  any  manner  yet  at  command  against  the  inoculation 
of  its  own  primary  tumor,  should  never  be  lost  sight  of  in  evaluating 
descriptions  of  therapeutic  experiments,  for  it  demonstrates  beyond 
reasonable  doubt  that  cancer  cells  proliferating  in  an  animal  to  which 
they  are  not  native  are  doing  so  under  a  certain  disadvantage.  A  pro- 
cedure, therefore,  able  to  turn  the  tide  against  them  might  still  be 
ineffectual  when  appHed  against  malignant  cells  more  favorably 
situated  in  an  animal  to  which  they  are  autochthonous.  Furthermore, 
the  almost  uniform  success  with  which  the  cancer  cell  can  be  ingrafted 
in  the  organism  within  which  it  first  acquired  malignant  properties, 
as  contrasted  with  any  other  organism,  mihtates  very  strongly  against 
any  parasitic  theory  of  tumor  genesis.     At  the  same  time,  the  observa- 


272  GENERAL    SUMMARY 

tion  that  the  bearer  of  a  tumor  offers  a  particularly  favorable  soil  for 
the  cells  of  that  neoplasm  will  intimate  to  the  surgeon  the  necessity 
for  a  continuance  of  the  most  extreme  care  against  the  distribution  of 
cancer  cells  throughout  the  operation  wound,  a  precaution  already 
suggested  in  the  past  by  the  frequency  of  local  recurrence  following  the 
excision  of  mahgnant  tumors.  Secondary  growth  along  the  needle 
track  after  exploratory  puncture  of  a  tumor  furnishes  an  even  more 
striking  example  from  human  pathology  of  this  extreme  susceptibility 
of  the  individual  to  inoculation  with  his  own  neoplasm.  Finally, 
these  considerations  demonstrate  how  minimal  is  the  chance  of  the 
transfer  of  cancer  from  one  individual  to  another  in  the  ordinary  course 
of  events. 

The  proliferation  of  a  tumor  after  its  introduction  into  another  host 
is  an  example,  not  of  infection,  but  of  transplantation;  the  paren- 
chymal cells  of  the  resulting  growth  are  derived,  not  from  the  elements 
of  the  new  host,  but  from  those  of  the  transferred  graft.  These  cells 
are  supported  and  nourished  by  a  stroma  which,  built  up  by  the  con- 
nective tissues  and  blood  vessels  of  the  new  organism,  is  well  on  its 
way  toward  completion  by  the  third  or  fourth  day  following  trans- 
plantation. 

Propagable  tumors  are  subject  to  fluctuations  in  growth  energy. 
They  may  grow  progressively,  or  disappear  spontaneously.  Even 
under  optimum  conditions,  however,  the  proUferative  power  of  the 
cancer  cell  falls  far  short  of  that  possessed  by  the  bacteria,  and  per- 
haps even  of  that  displayed  by  the  cells  of  the  developing  embryo. 
The  key  to  the  nature  of  the  malignant  cell  lies,  therefore,  not  in  the 
explanation  of  augmented  growth  power,  but  rather  in  an  elucidation 
of  the  capacity  of  this  cell  for  continuous  growth. 

A  tumor  under  cultivation  usually  retains  unaltered  the  characteris- 
tics of  the  primary  growth.  While  most  transplantable  neoplasms 
show  a  marked  deviation  from  the  normal  structure  of  the  organ  which 
gave  them  origin,  this  is  by  no  means  an  invariable  rule,  since  com- 
plete loss,  or  even  latency,  of  differentiation  is  not  necessary  for  con- 
tinuous growth,  and  tumors  which,  under  the  microscope,  are  dis- 
tinguishable from  their  mother  tissue  only  with  difficulty,  have  been 
proved  capable  of  unlimited  propagation.  So  far,  then,  as  the  re- 
tention of  normal  structure  is  a  criterion  of  innocence  its  significance 


GENERAL   SUMMARY 


273 


has  been  lost,  a  situation  parallel  to  that  obtaining  among  certain 
tumors  of  the  thyroid  gland  and  the  ovary  in  man. 

The  cells  of  a  few  transplantable  carcinomata  have  been  found 
capable  of  causing  a  transmutation  of  the  stroma  in  the  course  of  which, 
acquiring  malignant  properities,  it  becomes  indistinguishable  from 
other  sarcomata  of  the  mouse. 

Mice  in  which  tumors  have  undergone  partial  or  complete  absorption 
are  refactory  to  subsequent  transplantation,  either  of  the  same  or  of 
another  growth.  '  This  condition  of  resistance  is  brought  about  also 
by  the  absorption  of  hving  and  intact  cells  of  the  same  species,  but 
not  those  of  the  animal  itself.  Immunity,  once  induced,  cannot  be 
transferred  passively  to  other  animals  either  by  the  cells  or  the  body 
fluids,  although  it  is  probably  these  agents  which  are  responsible  for 
the  spread  of  the  condition  throughout  the  organism  within  which  it 
has  been  engendered.  And  while  there  is  a  certain  amount  of  evidence 
in  favor  of  the  fact  that  natural  resistance  may  be  the  outcome  of 
hereditary  transmission,  there  is  none  to  show  that  acquired  immunity 
can  be  so  transferred. 

Immunity  has  been  attributed  to  a  lack  of  the  specific  nutritive 
materials  necessary  for  tumor  growth.  On  the  other  hand,  it  has  been 
described  as  a  suppression  of  the  stroma  reaction  which,  under  more 
favorable  conditions,  would  have  undertaken  the  support  of  the  tumor 
in  its  new  host.     The  latter  supposition  has  more  evidence  in  its  favor. 


It  must  be  frankly  confessed  that  so  far,  at  least,  the  study  of  cancer, 
instead  of  affording  an  understanding  of  the  nature  of  the  disease,  has 
but  opened  up  new  problems  which  were  formerly  not  even  conceived. 
Hence  earnest  students  have  had  to  content  themselves  with  slowly 
and  laboriously  collecting  data,  in  the  hope  that  at  some  future  time 
these  may  be  combined  into  a  coherent  whole.  Slow  at  the  best,  this 
is  nevertheless  the  only  way  in  which  the  goal  can  be  surely  attained, 
for  the  empirical  method,  in  spite  of  its  centuries  of  effort,  has  pro- 
duced nothing  nearer  to  a  cure  than  surgical  removal.  'The  hope 
of  substituting  some  plan  of  specific  treatment  for  this  crude  and  only 
too  often  inefficient  means,  rests  on  the  fact  that  in  many  mice  trans- 
planted tumors,  and  in  a  few,  spontaneous  tumors,  have  vanished 
completely,  although  it  must  be  admitted  that  we  have  not  yet  the 
slightest  insight  into  the  mechanism  by  which  this  occurs.     Still,  the 


274  GENERAL   SUMMARY 


balance  must  be  very,  delicate,  j  the  margin  between  continuous  proKf- 
eration  and  cessation 'very  narrow,  and  the  newer  conceptions  of 
malignant  growth  encourage  the  hope  that  at  some  time,  far  in  the 
future  though  it  may  be,  the  nature  of  this  difference  will  be  unriddled, 
and  the  dream  of  effectual  interference  with  incessantly  proliferating 
cells  will  become  an  actuaUty.    (,;^^^  ,^  m  .  jj,  ,y^^^^^  ^  ^  ^^ j 


INDEX    OF   AUTHORS 


Adam,  on  homoplastic  transplantation,  42 
Adami,  on  cancer  houses,  43 ;  on  cancerous  de- 
generation, 12 
Alberts,  on  heteroplastic  transplantation,  51 
Albrecht  and  Hecht,  on  age  and  susceptibiHty, 
130 ;  on  amyloid  degeneration,  95  ;  on  para- 
biosis, 25S  (footnote) ;  on  pregnancy  and 
susceptibility,  138 ;  on  race  and  susceptibiHty, 
136;  on  sarcoma  development,  122;  on 
Scharlach  R,  37;  on  the  specificity  of  im- 
munity, 143. 
Alibert,  on  homoplastic  transplantation,  43 
Apolant,  on  the  action  of  radium,  261;  on 
athrepsia,  163,  166;  on  autoplastic  trans- 
plantation, 224;  on  classification,  214;  on 
the  frequency  of  cancer  in  mice,  199;  on  the 
genesis  of  mouse  tumors,  185,  186,  187;  on 
the  hare  tumor  of  v.  Dungern,  156 ;  on  hyper- 
sensibiUty,  182;  on  immunity  with  alien 
tissues,  148;  on  immunity  and  histology,  107  ; 
on  infiltrative  growth,  192;  on  lactation  and 
aetiology,  200;  on  transmissible  lympho- 
sarcoma of  the  dog,  233 ;  on  the  malignancy 
of  mouse  tumope,  193;  on  sarcoma  develop- 
ment, 112,  113;  on  spindle-shaped  epithehal 
cells,  106;  on  spontaneous  absorption,  90; 
on  the  stroma  of  hemorrhagic  tumors,  109; 
on  sweat  glands  in  the  mouse,  185 ;  on  the 
transplantation  of  timior  mixtures,  79,  171  ; 
on  variations  during  transplantation,  105 ; 
on  virulence,  62 ;  see  also  Ehrlich  and 
Apolant 
Apolant  and  Ehrlich,  on  the  transplantation 

of  tumor  mixtures,  79 
Apolant  and  Marks,  on  immunity  with  autol- 
ogous tissues,  150 
Arndt,  on  Egyptian  medicine,  i 
Askanazy,  on  pregnancy  and  growth,  28;    on 

the  production  of  tumors,  27 
AuBERTiN,  see  Marie  and  Aubertin 
Ayson,  on  thyroid  adeno-carcinoma  in  the  trout, 
237 

Baber,  on  non-encapsulation  of  the  thyroid,  241 
Baeslack,  on  infiltrative  growth,  191 ;  see  also 
Gaylord,  Clowes,  and  Baeslack,  and 
Clowes  and  Baeslack 
Basheord,  on  acquired  immunity,  139,  144;  on 
aetiology,  6,  9,  210;  on  age  and  susceptibility, 
129;  on  autoplastic  transplantation,  223; 
on  the  distribution  of  immunity,  153;  on 
dosage,  69,  73 ;   on  the  duration  of  immunity, 


154;  on  growth  rate,  84;  on  health  and 
susceptibility,  137;  on  heredity  and  aetiology, 
201,  204;  on  histological  structure,  109;  on 
immunity  with  ahen  tissues,  143,  148 ;  on  im- 
munity with  devitalized  tissues,  149  (foot- 
note);  on  the  infectivity  of  cancer,  198;  on 
inoculation  site,  76 ;  on  race  and  susceptibility, 
132;  on  sarcoma  development,  in;  on  the 
specificity  of  immunity,  142,  147 ;  on  spon- 
taneous absorption,  91 ;  on  the  stroma  of 
hemorrhagic  tumors,  109;  on  the  technic  of 
inoculation,  70;  on  treatment,  257,  268;  on 
variations  during  transplantation,  100,  loi ; 
on  virulence,  65 

Bashford  and  Mi-rray,  on  age  and  suscepti- 
biUty,  129  ;  on  early  stages,  59 ;  on  the  genesis 
of  mouse  tumors,  186;  on  heredity  and  aetiol- 
ogy, 202;  on  heterotypical  mitosis,  18;  on 
infiltrative  growth,  191;  on  the  malignancy 
of  mouse  tumors,  192;  on  metastasis,  190; 
on  pregnancy  and  susceptibiHty,  137;  on 
race  and  susceptibility,  132 ;  on  the  re-inocu- 
lation of  tumor-bearing  animals,  167;  on  the 
zoological  distribution  of  cancer,  184 

Basheord,  Ml-rray,  and  Bowen,  on  age,  race, 
and  susceptibiHty,  76;  on  diminished  trans- 
plantability,  78 ;  on  fluctuations  in  growth 
energy,  86;  on  spontaneous  absorption,  91 

Basheord,  Mltrr.\y,  and  Cr.4mer,  on  acquired 
immunity,  139;  on  adaptation,  225  ;  on  auto- 
plastic transplantation,  223;  on  the  cHnical 
course  of  transplanted  tumors,  92 ;  on  the 
distinction  between  tumors  and  inflammatory 
swelUngs,  78;  on  the  distribution  of  im- 
munity, 153;  on  the  duration  of  immunity, 
154;  on  early  stages,  59;  on  fluctuations  in 
growth  energy,  85 ;  on  the  frequency  of  cancer 
in  mice,  199;  on  variations  during  trans- 
plantation, 99;  on  the  histology-  of  receding 
tumors,  91;  on  infiltrative  growth,  191,  192; 
on  the  transmissible  lympho-sarcoma  of  the 
dog,  230;  on  metastasis,  190;  on  the 
optimum  conditions  of  transplantation,  88 ; 
on  phagocytosis  in  spontaneous  absorption, 
92 ;  on  the  propagation  of  hemorrhagic 
tumors,  72;  on  race  and  susceptibiHty,  132; 
on  the  relative  importance  of  soil  and  graft, 
72;  on  sarcoma  development,  no;  on  the 
specificity  of  immunity,  142;  on  spontaneous 
absorption,  91 ;  on  the  development  of  spon- 
taneous tumors  during  immunity,  128;  on 
the    stroma    of    hemorrhagic    tumors,    109; 


275 


-^ 


276 


INDEX  OF  AUTHORS 


on  the  action  of  radium,  261 ;  on  tumors  of 
the    mouse,    188;  on  virulence,  66 

Bashford,  Murray,  and  Haaland,  on  aher- 
nations  in  biological  quahties  of  the  tumor 
cell,  75  ;  on  athrepsia,  167  ;  on  the  hereditary 
transmission  of  immunity,  158;  on  hyper- 
susceptibility,  180;  on  immunity  in  tumor- 
bearing  animals,  151;  on  passive  resistance, 
156;  on  sarcoma  development,  115;  on  the 
specificity  of  immunity,  142 ;  on  the  develop- 
ment of  spontaneous  tumors  during  immunity, 
128 

Bashford,  Murray,  Haaland,  and  Bo\ven,  on 
adaptation,  65  ;  on  growth  energy,  8g  ;  on  race 
and  susceptibiHty,  132;  on  the  technic  of  in- 
oculation, 70 

Bashford  and  Russell,  on  athrepsia,  168;  on 
spontaneous  absorption,  go 

Beard,  on  aetiology,  18;   on  treatment,  260 

Beck,  on  treatment,  263 

Beckton,  on  Altmann's  granules,  193;  see  also 
CoLWELL  and  Beckton 

Beckton  and  Colwell,  on  Altmann's  granules, 
194 

Beckton  and  Russ,  on  Altmann's  granules, 
194 

Beebe,  on  treatment,  235 ;  see  also  Crile  and 
Beebe 

Beebe,  and  Ewing,  on  the  transmissible 
lympho-sarcoma  of  the  dog,  232,  233 

Beebe  and  Tracy,  on  treatment,  235 

Behla,  on  homoplastic  transplantation,  42 

Beneke,  on  kataplasia,  16 

Bensley,  on  Altmann's  granules,  194 

Benthin,  on  atypical  epithelial  growth,  36 

Bergel,  on  a  fat-sphtting  ferment  in  lym- 
phocytes, 37 

Bergell  and  Sticker,  on  treatment,  235 

V.  Bergmann,  on  autoplastic  transplantation,  45 

Billroth,  on  heteroplastic  transplantation,  51 

BiRCH-HiRSCHFELD  and  Garten,  on  the  pro- 
duction of  tumors,  22 

Blumenthal,  on  treatment,  259;  on  the  depo- 
sition of  arsem'c,  267  ;  see  also  v.  Leyden  and 
Blumenthal 

Bonnet,  on  thyroid  adeno-carcinoma  of  the 
trout,  236 

BoRREL,  on  athrepsia,  165;  on  immunity,  140, 
146;  on  the  infective  nature  of  tumors,  195; 
on  the  interval  after  which  growth  becomes 
apparent,  77;  on  metastasis,  190;  on  para- 
sites and  ffitiology,  195,  196 ;  on  the  per- 
centage of  success,  71 ;  on  squamous  cell 
carcinoma,  188;  on  treatment,  257  ;  on  trans- 
plantation, 57 

BoRREL  and  Petit,  on  autoplastic  transplanta- 
tion, 223 

BoRRMANN,  on  setiology,  13 

Borst,  on  setiology,  13 

BowEN,  see  Bashford,  Murray,  and  Bowen, 


and    Bashford,    Murray,    Haaland,    and 
Bowen 
Boycott,  on  uterine  tumors  in  the  rabbit,  22 
Bridre,  on  athrepsia,  166;    on  immunity,  140, 
144,   146,   154;    on  the  interval  after  which 
growth  becomes  apparent,  77 ;    on  parasites 
and    Eetiology,    196;     on    passive    resistance 
156;    on  pregnancy   and  susceptibility,    138; 
on  the  premetastatic  stage,  152;    on  the  re- 
sistance of  the  cancer  cell,  82 ;    on  treatment, 
257  ;    on  the  technic  of  inoculation,  68 
Bridre  and  Conseil,  on  parasites  and  aetiology, 

196 
Brodie-Mills,  on  horn  core,  6 
Brosch,  on  atypical  epithelial  growth,  22 
Brown,  on  the  nucleus,  3 
BuDD,  on  homoplastic  transplantation,  41 
Burgess,  on  the  stroma  reaction  in  immunity, 

176 
BuRKHAEDT,  on  Altmann's  granules,  194 
Burrows,  on  tissue  cultivation  in  mtro,  124,  126 ; 

see  also  Carrel  and  Burrows 
Buschke,  on  age  and  susceptibihty,  129 
BuTLiN,  on  autoplastic  transplantation,  44,  46 ; 
on  homoplastic  transplantation,  39 

Calkins,  on  rhythms  of  growth,  88 

Carmalt,  on  the  ameboid  motion  of  cancer  cells, 

S 

Carrel,  on  tissue  cultivation  in  vitro,  125,  126 

Carrel  and  Burrows,  on  tissue  cultivation  in 
vitro,  124,  126 

Caspari,  see  Neuberg  and  Caspari,  and  Neu- 
BERG,  Caspari,  and  Lohe 

Casper,  on  the  zoological  distribution  of  cancer, 
184 

Cazin,  see  Duplay  and  Cazin 

Celsus,  on  classification,  i 

Chalmers  and  Perry,  on  aetiology,  6 

Chisholm,  on  the  blood  of  rats  bearing  trans- 
plantable sarcoma,  96 

Clowes,  on  the  hereditary  transmission  of 
immunity,  157  (footnote) ;  on  immunity,  141, 
143  ;  on  race  and  susceptibihty,  132  ;  on  re- 
inoculation,  164;  on  the  resistance  of  the 
cancer  cell,  81 ;  on  spontaneous  absorption, 
90,  138;  on  the  technic  of  inoculation,  71 ;  on 
treatment,  257;  see  also  Gaylord  and 
Clowes,  and  Gaylord,  Clowes,  and  Baes- 
lack 

Clowt.s  and  Baeslack,  on  age,  race,  and  sus- 
ceptibility, 76 ;  on  the  distinction  between 
tumors  and  inflammatory  swelUngs,  78;  on 
dosage,  73;  on  immunity,  139,  141,  155;  on 
the  interval  after  which  growth  becomes 
apparent,  77  ;  on  spontaneous  absorption,  91; 
on  the  stimulation  of  growth  energy,  68 

Clunet,  on  the  histology  of  tumors  after  ex- 
posure to  X-rays,  260;  on  sarcoma  develop- 
ment, 123;   on  sarcoma  developing  after  ex- 


INDEX    OF    AUTHORS 


277 


posure  to  X-rays,  30 ;   on  the  development  of 

spontaneous  tumors  during  immunity,    128; 

see  also  !Marie  and  Clunet 
Coca,  on  treatment,  26g ;    see  also  v.  Dungern 

and  Coca 
Coca,  Dorrance,  and  Lebredo,  on  treatment, 

268 
Coca  and  Oilman,  on  treatment,  268 
CoH>'HEiii,  on  aetiolog>',  8 
CoLWELL,  see  Beckton  and  Col-well 
CoLWELL  and  Beckton",  on  Altmann's  granules, 

194 
CoxsEiL,  see  Brjdre  and  Conseil 
CoNT.AJinN,  on  the  action  of  X-rays,  261 
CoPEiLA.x   and   Hake,    on    the   acidity    of   the 

gastric   contents    in    tumor-bearing    animals, 

97 
CoRNiL,  on  autoplastic  transplantation,  49 
Cramer,  on  metaboHsm  in  tumor-bearing  rats, 

97 ;      see     also    Basheord,     Mltibay,     and 

CR.AilER 

Cramer  and  Prixgle,  on  metabohsm  in  tumor- 
bearing  rats,  98 

Crile  and  Beebe,  on  treatment,  235 

CRITZM-A.XX,  on  the  relation  between  twin  births 
and  cancer,  18 

CuEN'OT  and  Mercler,  on  the  hereditary  trans- 
mission of  immunity,  159;  on  the  hereditary 
transmission  of  susceptibiUty,  158;  on  preg- 
nancj'  and  susceptibility,  138;  on  race  and 
susceptibilitj%  136 

Da\idsohn,    on    amyloid    degeneration    in   the 

white  mouse,  96 
Deton,  on  the  genesis  of  mouse  tumors,  187 
DoRR-ANCE,  see  Coca,  Dorr-\nce,  and  Lebredo 
DtDGEON,     see     Shattock,     Seligm.a.nx,   and 

DlT)GE0N 

V.  Dl"xgerx,  on  immunity,  155;  on  the  trans- 
missible lympho-sarcoma  of  the  dog,  235  ;  on 
passive  resistance,  155 

V.  Dl^stgerx  and  Coca,  on  immunity,  172; 
on  a  transmissible  sarcoma  of  the  hare,  235 

Duplay  and  Cazln,  on  heteroplastic  transplan- 
tation, 52 ;  on  the  transmissible  lympho- 
sarcoma of  the  dog,  227 

Dltuytrex,  on  heteroplastic  transplantation, 
50 

Eberth  and  Splde,  on  the  genesis  of  mouse 
tumors,  185 

Edelfsen  and  Hensen,  oh  growth  and  preg- 
nancy, 98 

Ehrexreich  and  jMich-AELis,  on  the  zoological 
distribution  of  cancer,  184 

Ehrlich,  on  the  resistance  of  the  cancer  cell,  82  ; 
on  inoculation  site,  77 ;  on  the  percentage  of 
success,  71;  on  the  technic  of  inoculation,  69 ; 
on  the  stimulation  of  growth  energy,  68 ;  on 

■   the    stroma    reaction,    61 ;      on   increase   of 


\-irulence,  62 ;  on  the  stroma  in  hemorrhagic 
tumors,  109;  on  sarcoma  development,  no, 
113;  on  passive  resistance,  156;  on  immunitj% 
140,  141,  154,  159;  on  the  transplantation  of 
tumor  mixtures,  79 ;  on  pregnancy  and  sus- 
ceptibility, 138;  on  sex  and  susceptibiUty, 
137;  on  the  limits  of  transplantation,  129;  on 
athrepsia,  159,  169;  on  spontaneous  absorp- 
tion, 220;  on  aetiology,  208;  on  chondroma 
in  the  mouse,  188;  see  also  Apolant  and 
Ehrlich 

Ehrlich  and  Apolant,  on  age  and  susceptibility, 
130 ;  on  the  frequency  of  cancer  in  mice,  199  ; 
on  sarcoma  development,  109,  in,  112,  113; 
on  spontaneous  carcinoma  sarcomatodes,  188 

Ehrlich,  H.,  see  Kr.\us,  R.anzi,  and  H.  Ehrlich 

V.  Eiselsberg,  on  a  transplantable  sarcoma  of 
the  rat,  54 

EwTNG,  on  autoplastic  transplantation,  44,  48 ; . 
on  thjToid  adeno-carcinoma  of  the  trout,  241  ; 
on  tissue  cultivation  in  vitro,  126;  see  also 
Beebe  and  Ewing 

Fallopius,  on  diagnosis  and  treatment,  3 

Da  Fano,  on  the  relation  of  plasma  cells  and 

Ij-mphocytes  to  immunity,  176;  on  the  dis- 
tribution of  immunity,   153 
Farmer,  Moore,  and  Walker,  on  heterotj-pi- 

cal  mitosis,  17 
Fere,  on  the  growth  of  transplanted  tissues  in 

brooding  hens,  28 
FiCHERA,  on  pregnancy  and  susceptibility,  28, 

138 ;  on  treatment,  268 ;  on  the  production  of 

tumors,  28 
Fiebiger,    on    the    zoological    distribution    of 

cancer,  184 
FixsTERER,  see  Pfeiffer  and  Finsterer 
FiRKET,  on  a  transplantable  sarcoma  of  the  rat, 

55 
Fischer,  on  atypical  epithelial  growth,  30 
Fischer,  E.,  on  treatment,  265 
Fleischmaxx,    see   Michaelis,    Fleischmann, 

and  PiNCUSSOHN 
Flexner,  on  heteroplastic  transplantation,   52 

(footnote) 
Flexner  and  Joblixg,  on  adeno-carcinoma  in 

the  rat,    188;   on  the  duration  of  immunity, 

155;    on  hypersusceptibihty,  178;    on  immu- 

nitj',  139,  140;  on  inoculation  site,   77;   on 

metastasis,   191  ;    on  the  premetastatic  stage, 

153 
FoLLiN,  on  heteroplastic  transplantation,  51 
Fraenkel,  on  the  production  of  tumors.  22 
Frank  and  Unger,  on  hormones,  259  (footnote) 
Frel'N'd,  on  pregnancy  and  growth,  29;   on  the 

production  of  tumors,  27 
Freytag,    on    am3doid    degeneration,    95 ;     on 

treatment,  258 
FujiNAin   and   Inamoto,    on    a   transplantable 

tumor  of  the  fowl,  244 


278 


INDEX  OF  AUTHORS 


Galen,  on  aetiology  and  treatment,  2 

Garten,  see  Birch-Hirschfeld  and  Garten 

Gay,  on  hypersusceptibility,  180;  on  passive  re- 
sistance, 156 ;  on  the  premetastatic  stage,  153  ; 
on  race  and  susceptibility,  136 ;  on  the  trans- 
plantation of  metastases,  yg ;  on  treatment,  258 

Gaylord,  on  hypersusceptibility,  179;  on  passive 
resistance,  157  ;  on  the  resistance  of  the  cancer 
cell,  81 ;  on  thyroid  adeno-carcinoma  of  the 
trout,  239,  240,  241,  243  ;  on  treatment,  236 

Gaylord  and  Clowes,  on  cancer  cages,  197 ;  on 
dosage,  73 ;  on  spontaneous  absorption,  91, 
92,  139 

Gaylord,  Clowes,  and  Baeslack,  on  sponta- 
neous absorption,  138 

Geissler,  on  the  transmissible  lympho-sarcoma 
of  the  dog,  228 

Gierke,  on  age  and  susceptibility,  130;  on 
athrepsia,  162,  168;  on  classification,  220;  on 
metastasis,  191 ;  on  race  and  susceptibility, 
134;  on  histology  and  malignancy,  107;  on  sex 
and  susceptibility,  137;  on  the  specificity  of 
immunity,  142  ;  on  the  stroma  reaction,  61  ; 
on  the  technic  of  inoculation,  70 

GiLMAN,  see  Coca  and  Gilman 

Gilruth,  on  thyroid  adeno-carcinoma  of  the 
trout,  237 

Goldmann,  on  parabiosis,  259  (footnote) ;  on 
inoculation  site,  77 

Gosio,  on  the  reduction  of  selenium  and  tel- 
lurium by  bacteria,  264 

Gougerot  and  Laroche,  on  the  production  of 
tumors,  29 

Grawitz,  on  slumber  cells,  18 

Greischer,  on  atypical  epithelial  growth,  35 

GrtJnbaum,  a.  and  H.,  on  treatment,  259,  260 

Gudernatsch,  on  non-encapsulation  of  the  trout 
thyroid,  240 

Guelliot,  on  homoplastic  transplantation,  40 

Haaland,  on  age  and  susceptibility,  130;  on 
autoplastic  transplantation,  209,  224;  on 
the  resistance  of  the  cancer  cell,  83 ;  on  the 
frequency  of  cancer  in  mice,  200;  on  health 
and  susceptibility,  137  ;  on  hypersusceptibility, 
181 ;  on  immunity  with  devitalized  tissues, 
144,  149 ;  on  immunity  in  tumor-bearing  mice, 
151,  152;  on  inflammation  and  aetiology,  205; 
on  lactation  and  aetiology,  200 ;  on  metastasis, 
1 14,  190 ;  on  operative  removal  and  recurrence, 
222  ;  on  passive  resistance,  156 ;  on  pregnancy 
and  susceptibility,  137 ;  on  race  and  suscep- 
tibility, 133 ;  on  the  relative  resistance  of 
tumors  to  heat,  82  ;  on  sarcoma  development, 
113,  118;  on  the  specificity  of  immunity,  142; 
on  spontaneous  absorption,  221 ;  on  squam- 
ous cell  carcinoma,  188;  on  the  technic  of 
inoculation,  68,  69 ;  on  the  transplantation 
of  tumor  mixtures,  79 ;  on  tumors  of  the  mouse, 


188;  see  also  Bashford,  Mxjrray,  and 
Haaland,  and  Bashford,  Murray,  Haaland, 
and  Bowen 

Haendel,  see  Uhlenhuth,  Haendel,  and 
Steffenhagen 

Hahn,  on  autoplastic  transplantation,  48 

Hake,  see  Copeman  and  Hake 

Hamburger,  on  autoplastic  transplantation, 
46 

Hanau,  on  atypical  epithelial  growth,  21 ;  on 
a  transplantable  carcinoma  of  the  rat,  53 

Hanes,  see  Lambert  and  Hanes 

V.  Hansemann,  on  aetiology,  7 ;  on  the  analogy 
between  human  and  mouse  cancer,  193 ;  on 
anaplasia,  14,  16;  on  atypical  mitosis,  14; 
on  the  genesis  of  mouse  tumors,  185,  189;  on 
heterotypical  mitosis,  17;  on  the  trans- 
missible lympho-sarcoma  of  the  dog,  228- 
on  metastasis,  103,  193  ;  on  sarcoma  develop- 
ment, III  (footnote);  on  the  selective  action 
of  selenium,  265  ;  on  thyroid  adeno-carcinoma 
of  the  trout,  239 ;  on  heteroplastic  trans- 
plantation, 52 

Harrison,  on  tissue  cultivation  in  vitro,  124 

Hauser,  on  aetiology,  7,  12,  13 

Hecht,  see  Albrecht  and  Hecht 

Helmholz,  on  atypical  epithelial  growth,  32 

Hensen,  see  Edelfsen  and  Hensen 

Hericourt  and  Richet,  on  treatment,  267 

Hertwig,  on  aetiology,  9 

Hertwig  and  Poll,  on  athrepsia,  165;  on  im- 
munity, 141;  on  race  and  susceptibility,  132, 
133  ;   on  the  technic  of  inoculation,  71 

Herxheimer  and  Reinke,  on  the  relation  of 
lipoids  to  cell  division,  37 

Herzog,  on  a  transplantable  sarcoma  of  the  rat, 
188;   on  pregnancy  and  susceptibility,  137 

Heyde,  see  Sauerbruch  and  Heyde 

HiGUCHi,  on  immunity,  147,  148 

v.  HippEL,  on  the  production  of  tumors,  27 

Hippocrates,  on  cancer  of  the  breast,  i 

Hodenpyl,  on  treatment,  269 

Hofer,  on  thyroid  adeno-carcinoma  of  the  trout, 

237 
Hooke,  on  the  cellular  structure  of  cork,  3 

III  and  Miningham,  on  treatment,  269 
Inamoto,  see  Fujinami  and  Inamoto 

Jaboulay,  on  thyroid  adeno-carcinoma  of  the 
trout,  237 

Jacoby,  on  the  deposition  of  salicylic  acid,  267' 

Janeway,  on  aetiology,  14 

Jenny,  on  the  histology  of  Hanau's  rat  car- 
cinoma, 53 

Jensen,  on  acquired  immunity,  139;  on  diet 
and  susceptibiHty,  134;  on  early  stages,  58;: 
on  the  genesis  of  mouse  tumors,  185;  oa 
heredity  and  eetiology,  205 ;  on  the  interval 
after  which  growth  becomes  apparent,  77;  on 


INDEX   OF   AUTHORS 


279 


race  and  susceptibility,  130, 131 ;  on  the  resist- 
ance of  the  cancer  cell,  80 ;   on  selection,  141 ; 
on  spontaneous  absorption,  90 ;  on  the  technic 
of  inoculation,  68;    on  treatment,  256;    on  a 
transplantable  carcinoma  of  the  mouse,  56 ;  on 
a  transplantable  sarcoma  of  the  rat,  131,  188; 
on  a  transplantable  tumor  of  the  beet,  184; 
on  transplantation,  71 
Jentzer,  on  pregnancy  and  growth,  28 
Joachim,  on  Egyptian  medicine,  i 
JOBUNG,  on  the  premetastatic  stage,  iS3  ;  on  the 
re-inoculation  of  tumor-bearing  animals,  168; 
on  heteroplastic  transplantation,  52  ;    see  also 
Flexner  and  Jobling 
JOBSON,  see  Loeb  and  Jobson 
Jolly,  on  tissue  cultivation  in  vitro,  126 
JOREs',  on  atypical  epitheHal  growth,  31 
JUNCKER,  on  homoplastic  transplantation,  40 

Kautmann,  on  autoplastic  transplantation,  45  ; 
on  the  production  of  tumors,  21 

Keeling,  on  the  production  of  tumors,  23 

Keysser,  see  v.  Wassermann,  Keysser,  and 
Wassermann  . 

Klebs,  on  the  conjugation  of  leucocytes  with 
epithelial  cells,  17  ;  on  autoplastic  transplanta- 
tion, 45 ;  on  mitosis,  14;  on  heteroplastic 
transplantation,  52 

Klemperer,  on  treatment,  265 

KoKUBO,  on  aetiology,  13 

E.RASKE,  on  autoplastic  transplantation,  45       _ 

Kraus,  Ranzi,  and  H.  Ehrlich,  on  the  distri- 
bution of  immunity,  154 


Lack,  on  autoplastic  transplantation,  47  ;  on  th{ 

production  of  tumors,  21 
Lambert,  on  immunity  with  autologous  tissues, 

150 
Lambert  and  Hanes,  on  the  ameboid  motion 

of  cancer  cells,  5,  125;    on  tissue  cultivation 

in  vitro,  125,  126 
Lane-Claypon   and    Starling,    on   hormones, 

259 
Langenbeck,  on  heteroplastic  transplantation, 

50 
Lanz,  on  homoplastic  transplantation,  44 

Laro'che,  see  Gougerot  and  Laroche 
Lazarus-Barlow,    on    the    genesis    of    mouse 

tumors,  189 
Lebert,  on  heteroplastic  transplantation,  51 
Lebredo,  see  Coca,  Dorrance,  and  Lebredo 
Leitch,  on  hypersusceptibility,  181 ;   on  uterine 

carcinoma  in  the  rabbit,  22 
Lenhart,  see  Marine  and  Lenhart 
Leonides,  on  treatment,  2 
Leopold,  on  the  production  of  tumors,  21 
Leopold,  see  Loeb  and  Leopold 
Levin,  on  immunity,  149,  i5o,  iS4;    on  the  in- 
tense connective  tissue  reaction  of  rats,  33 ; 
•      on  the  production  of  tumors,  26 


Lewin,  on  age  and  susceptibihty,  130;  on 
athrepsia,  165;  on  immunity,  139,  142,  i43, 
146;  on  race  and  susceptibility,  135;  on  the 
resistance  of  the  cancer  ceU,  82 ;  on  sarcoma 
development,  118;  on  sex  and  susceptibility, 
137  ;  on  treatment,  258 ;  on  variations  during 
transplantation,  107;  see  also  Michaelis 
and  Lewin 
Lewin  and  Michaelis,  on  carcinoma  mammae 
in  the  rat,  188 ;  on  metastasis,  191  (footnote) 
v.  Leyden,  on  parasites  and   etiology,  59;    on 

treatment,  257 
V.  Leyden  and  Blumenthal,  on  treatment,  257 
Liepmann,  on  sarcoma  development,  115 
LwiNGOOD,  on  spontaneous  tumors  of  the  mouse, 

189  , 

Loeb,    L.,    on    etiology,      25;     on    age    and 
susceptibihty,     129;     on    autoplastic    trans- 
plantation,   223;    on    dosage,    73;    on  early 
stages,  59  ;    on  the  importance  of  soil,  72  ;  on 
metastasis,   190;   on  race  and  susceptibihty, 
131 ;   on  the  resistance  of  the  cancer  cell,  81 ; 
on  sarcoma  development,   113,  ii4.  "8;   on 
sex  and  susceptibility,  137;    on  spontaneous 
absorption,  90;    on  a  transplantable  sarcoma 
of   the   rat,   S7,   188;    on  the  production  of 
tumors,     24;      on     the     transplantation     of 
stationary  or  receding  tumors,  78 ;    see  also 
White  and  Loeb 
Loeb  and  Jobson,  on  carcinoma  in  cattle,   197 
Loeb  and  Leopold,  on  autoplastic  transplanta- 
tion, 223  ,  ,      , 
Loeb  and  White,  on  the  effect  of_  heat  upon 

growth,  latent  period,  and  absorption,  83 
Loeb   O.,  on  the  deposition  of  iodine,  267 
Lohe',  see  Neuberg,  Caspari,  and  Lohe 
LUBARSCH,  on  amyloid  degeneration,  95 


Marie  and  Aubertin,  on  uterine  carcinoma  in 
the  rabbit,  22  ,  i  ^ 

Marie  and  Clunet,  on  the  histology  of  tumors 
after  exposure  to  X-rays,  260 

Marine  and  Lenhart,  on  thyroid  adeno-carci- 
noma  in  the  trout,  242  ;   on  thyroid  histology, 

243  ,  - ,    ' 

Marks,  see  Apolant  and  Marks 
Martin,  on  the  production  of  tumors   21 
Maurer,  on  non-encapsulation  of  the  thyroid 

in  fish,  241  .  ,    ,.  ,  *u    ,T  • 

McConnell,  on  atypical  epithehal  growth,  31, 

on  heteroplastic  transplantation,  37 
McCoy,  on  the  zoological  distribution  of  cancer, 

MsmGRECEANU,  on  the  weights  of  organs  in 
tumor-bearing  animals,  93  ;  on  the_  amount 
of  food  ingested  by  tumor-bearing  animals,  94 

Mercier,  see  Cltenot  and  Mercier_ 

Metchnikofe,  on  parasites  and  stiologj',  52, 
see  also  Roux  and  Metchnikofe 

Meyer,  on  atypical  epithelial  growth,  35 


28o 


INDEX    OF    AUTHORS 


MiCHAELis,  on  athrepsia,  i66;  on  cancer  cages, 
197;  on  classification,  213  ;  on  the  distinction 
between  tumors  and  inflammatory'  swellings, 
78;  on  the  genesis  of  mouse  tumors,  186;  on 
immunity,  143 ;  on  the  stimulation  of 
growth  energy,  68 ;  on  infiltrative  growth,  igi, 
192 ;  on  the  inter^-al  after  which  growth 
becomes  apparent,  77 ;  on  metastasis,  191 ; 
on  passive  resistance,  156;  on  race  and 
susceptibility,  132 ;  on  the  resistance  of  the 
cancer  cell,  81 ;  on  selection,  141 ;  on  spon- 
taneous absorption,  90 ;  see  also  Ehrenreich 
and  MiCHAELis,  and  Lewin  and  Michaelis 

MiCHAELis  Fleischmann,  and  Pincussohn,  on 
immunity,  140,  142,  146 

Michaelis  and  Lewin,  on  variations  during 
transplantation,  107 

MiCHAtT),  on  the  deposition  of  iodine,  267 

Miller,  on  Altmann's  granules,  194 

MiLXER,  on  implantation  cancer,  49 

MixiNGHAM,  see  III  and  Miningham 

MiNOT,  on  growth  rate,  84 ;  on  pregnancy  and 
growth,  98 

Moore,  see  Farmer,  IMoore,  and  Walker 

Moore  and  Walker,  on  the  resistance  of  the 
cancer  cell,  81 

MoRAD,  on  the  hereditary  transmission  of  sus- 
ceptibihty,  157;  on  pregnancy  and  suscepti- 
bUity,  137 ;  on  a  transplantable  carcinoma 
of  the  mouse,  54 

MoRESCHi,  on  hypersusceptibUity,  180;  on 
unmunity  ■n'ith  alien  tissues,  148 ;  on  immunity 
■nith  normal  tissues,  146;  on  tumor  growth 
and  nourishment,  92 

De  Morgan,  on  jetiology,  18 

MuLLER,  on  the  cellular  structure  of  tumors,  3 

Mlt^jhy,  see  Rous  and  Mltlphy 

Murray,  on  adaptation,  65,  208;  on  the  chnical 
course  of  spontaneous  tumors,  221;  on  the 
frequency  of  cancer  in  mice,  199;  on  hepatic 
carcinoma  in  the  cow,  207 ;  on  heredity  and 
ffitiologj',  202,  204;  on  the  histology  of  car- 
cinoma mammje,  219;  on  immunity  and 
histologj%  108 ;  on  the  inter\-al  after  which 
growth  becomes  apparent,  77  (footnote) ;  on 
the  malignancy  of  mouse  tumors,  192 ;  on 
metastasis,  191 ;  on  spontaneous  absorption, 
220;  on  sweat  glands  in  the  mouse,  185;  on 
the  technic  of  inoculation,  70;  on  thinroid 
adeno-carcinoma  of  the  trout,  236;  on  a 
transplantable  keratinizing  adeno-carcinoma 
of  the  mouse,  100 ;  on  a  transplantable  osteo- 
chondro-sarcoma,  100 ;  on  the  transplantation 
of  metastases,  79 ;  on  tumors  of  the  mouse, 
188;  on  the  zoological  distribution  of  cancer, 
184;  see  also  Bashford  and  Mi^rray, 
Basheord,  Murray,  and  Bowen,  Bashford, 
Murray,  and  Cr.auer,  Basheord,  IMurray, 
and  H.^\LAXD,  and  Bashford,  Mutrray, 
Haaland,  and  Bowen 


Neuberg  and  Caspari,  on  treatment,  265 
Neuberg,  Caspari,  andLoHE,  on  treatment,  266 
Neve,  on  the  Kangri  basket,  6 
Newsholme,  on  cancer  houses,  43 ;   on  heredity 

and  aetiologj^  201 
Nichols,  on  the  production  of  tumors,  25 
NoviNSKY,    on    the    transmissible    Ijrmpho-sar- 

coma  of  the  dog,  227 

Oefele,  on  Egj'ptian  medicine,  i 
Oertel,  on  cancerous  degeneration,  12 
Ordway,  see  Tyzzer  and  Ordway 
Orth,  on  sarcoma  development,  118 
Oswald,  on  diffusion,  267 

Paracelsus,  on  Galen's  hypothesis,  3 

Pare,  on  treatment,  3 

Perry,  see  Chalmers  and  Perry 

Petersen,    on    aetiologj^,    13 ;     on    retrograde 

metastasis,  44 
Petit,  see  Borrel  and  Petit 
Peytulhe,     on    heteroplastic    transplantation, 

SO 
Pfelffer,    on    a    transplantable    melano-carci- 

noma  of  the  mouse,  53;  on  anaphylaxis,  182 
Pfelffer  and  Finsterer,  on  anaphylaxis,  182 
Pforringer,  on  aetiologj',  13 
Pick,  on  thyroid  a,deno-carcinoma  of  the  trout, 

238 
Pick  and  Poll,  on  the  genesis  of  mouse  tumors, 

18s  ;  on  thyroid  adeno-carcinoma  of  the  trout, 

238 
Pincussohn,  see  Michaelis,  Fleischm.a.nn,  and 

Pincussohn 
Plehn,  on  thyroid  adeno-carcinoma  of  the  trput, 

237,   238  (footnote),   239;  on  the  zoological 

distribution  of  cancer,  184 
Plicque,  on  irritation  and  aetiologj^  6 
PoDWYSSOZKi,  on  asymmetrical  mitosis,  15 
Poll,    see  Hert'wig  and  Poll,  and  Pick  and 

Poll 
Price-Jones,   on   the   blood   of   tumor-bearing 

mice,  96 
Pringle,  see  Cr.amer  and  Pringle 
Purvis,  on  thj^roid  adeno-carcinoma  of  the  trout, 

236 

Quincke,  on  autoplastic  transplantation,  47 

Ranzi,  on  anaphylaxis,  182;     see  also  K1r.\us, 

R.ANZI,  and  H.  Ehrlich 
Rautm,  on  Altmann's  granules,  194 
Regaud,  on  parasites  and  aetiology,  196 
Reicher,  on  treatment,  262 
Reinke,  on  atypical  epithelial  growth,  26;    see 

also  HERXHEiiiER  and  Reinke 
Remak,  on  cell  division,  4 
Ribbert,  on  aetiology,   10;    on  anaplasia,    16; 

on  asymmetrical  rnitosis,  15 ;    on  autoplastic 

transplantation,  224;    on  heteroplastic  trans- 


INDEX    OF    AUTHORS 


281 


plantation,  52,  224 ;  on  the  production  of 
tumors,  23 

Richardson,  on  autoplastic  transplantation,  47 

RrcHET,  see  Heeicourt  and  Richet 

Rous,  on  hypersensibility,  182;  on  parabiosis, 
259;  on  pregnancy  and  transplantation,  28; 
on  the  specificity  of  immunity,  147  ;  on  a  trans- 
missible sarcoma  of  the  fowl,  244 ;  on  the 
production  of  tumors,  29;  on  tumor  growth 
and  nourishment,  93 

Rous  and  Murphy,  on  a  transmissible  sarcoma 
of  the  fowl,  244 

Rous,  Murphy,  and  Tytler,  on  a  transmissible 
sarcoma  of  the  fowl,  244 

Roux  and  Metchnikoff,  on  heteroplastic 
transplantation,  52 

RovsiNG,  on  treatment,  268 

Russ,  see  Beckton  and  Russ 

Russell,  on  extirpation  and  immunity,  163; 
on  the  stroma  reaction  in  immunity,  174;  on 
the  immunization  of  tumor-bearing  animals, 
151;  on  the  duration  of  immunity,  155;  on 
antibodies  in  immunity,  157 ;  on  sarcoma  de- 
velopment, no,  122;  see  also  Bashford 
and  Russell 

Sailer,  on  the  inoculability  of  carcinoma,  57 
Sauerbruch  and  Heyde,  on  parabiosis,  258 
Saul,  on  parasites  and  aetiology,  196 
Schleiden,  on  the  cellular  structure  of  plant 

tissues,  3 
Schmidt,  on  pulmonary  tumor  emboli  in  man, 

IIS 
Schmincke,  on  atypical  epithelial  growth,  35 ; 

see  also  Wacker  and  Schmincke    ' 
ScHONE,  on  athrepsia,  161 ;  on  immunity  with 

embryo,  14s ;   on  the  specificity  of  immunity, 

147 ;   on  immunity  in  tumor-bearing  animals, 

ISO 
Schwann,  on  the    cellular   structure  of  animal 

tissues,  3 
Scott,  on  thyroid  adeno-carcinoma  of  the  trout, 

236 
Seligmann,    see    Shattock,    Seligmann,   and 

Dudgeon 
Senn,  on  homoplastic  transplantation,  43 ;    on 

autoplastic  transplantation,  49 
Seyberth,   on  bladder  tumors  in   aniline   dye 

workers,  33 
Shattock,  on  uterine  carcinoma  in  the  rabbit,  22 
Shattock,  Seligmann,  and  Dudgeon,  on  preg- 
nancy and  growth,  28     , 
Smith,  on  homoplastic  transplantation,  42 
Smith  and  Washbourn,   on  the  transmissible 

lympho-sarcoma  of  the  dog,  228 
Snow,  on  atypical  epithelial  growth,  32 
Spiess,  on  treatment,  262 
Spude,  see  Eberth  and  Spltde 
Stahr,  on  atypical  epithelial    growth,  33 ;    on 

the    interval    after    which    growth    becomes 


apparent,  77;  on  the  production  of  tumors, 
23,  188;  on  race  and  susceptibility,  135;  on 
sarcoma  development,  123;  on  the  technic  of 
inoculation,  71 

Starling,  see  Lane-Claypon  and  Starling 

Steffenhagen,  see  Uhlenhuth,  Haendel,  and 
Steffenhagen 

Sticker,  on  the  transmissible  lympho-sarcoma  of 
the  dog,  228  ;  on  the  premetastatic  stage,  152  ; 
on  sarcoma  development,  118;  on  treatment, 
23s ;  on  the  zoological  distribution  of  cancer, 
184;  see  also  Bergell  and  Sticker 

Stockard,  on  non-encapsulation  of  the  trout 
thyroid,  240 

Stoeber,  on  atypical  epithelial  growth,  34 

Stoeber  and  Wacker,  on  atypical  epithelial 
growth,  34 

Stroebe,  on  asymmetrical  mitosis,  16 

Takemura,  on  the  deposition  of  iodine,  267 
Thiersch,  on  aetiology,  s,  6;   on  metastasis,  5 
Thorel,   on   the   development   of   spontaneous 

tumors  during  immunity,  128 
Thorn,  on  autoplastic  transplantation,  46,  47,  49 
V.  Tiesenhausen,  on  the  production  of  tumors, 

27 
TR.ACY,  see  Beebe  and  Tracy 
TuLPius,  on  homoplastic  transplantation,  40 
Tytler,  see  Rous,  Murphy,  and  Tytler 
Tyzzer,  on  the  hereditary  transmission  of  im- 
munity and  susceptibility,  157;    on  heredity 
and  aetiology,  204 ;  on  race  and  susceptibility, 
136 
Tyzzer   and   Ordway,    on   the   zoological   dis- 
tribution of  cancer,  184 

Uhlenhuth,  Haendel,  and  Steffenhagen,  on 
athrepsia,  162;  on  the  distribution  of  im- 
munity, 154;  on  dosage,  75  ;  on  the  duration 
of  immunity,  155  ;  on  hypersusceptibiHty,  181 ; 
on  passive  resistance,  157 ;  on  treatment,  259, 
263 

Uhlenhuth  and  Weidanz,  on  immunity,  147, 
149;  on  pregnancy,  and  susceptibiHty,  137; 
on  race  and  susceptibility,  136;  on  the  re- 
sistance of  the  cancer  cell,  83 ;  on  the  trans- 
plantation of  metastases,  79 ;  on  treatment, 
263 

Unger,  see  Frank  and  Unger 

von  den  Velden,  on  treatment,  266 

Velich,  on  a  transplantable  sarcoma  of  the  rat, 

55  _ 

Verse,  on  aetiology,  13 

Vesalius,  on  Galen's  hypothesis,  3 

ViDAL,  on  treatment,  260,  269 

Viel-Hautmesnil,  on  homoplastic  transplanta- 
tion, 41,  50 

Virchow,  on  aetiology,  4;  on  the  analogy  be- 
tween tumor  cell  and  ovum,  1 7 ;  on  autoplastic 


282 


INDEX    OF    AUTHORS 


transplantation,  48 ;    on  heteroplastic  trans- 
plantation, SI ;  on  metastasis,  4 

Wacker,  see  Stoeber  and  Wacker 

Wacker  and  Schmincke,  on  atypical  epithelial 

growth,  36 
Wade,    on    the    transmissible    lympho-sarcoma 

of  the  dog,  234 
Wakasugi,  on  autoplastic  transplantation,  47 
Waldeyer,  on  aetiology,  5,  7 
Walker,    on    treatment,    258,    265 ;     see    also 

Farmer,  Moore,  and  Walker,  and  Moore 

and  Walker 
Walker  and  Whittingham,  on  heterotypical 

mitosis,  18 
Washbourn,  see  Smith  and  Washbourn 
Wassermann,  see  v.  Wassermann,  Keysser, 

and  Wassermann 
V.  Wassermann,  Keysser,  and  Wassermann, 

on  treatment,  263 
Wehr,  on  the  transmissible  lympho-sarcoma  of 

the  dog,  227 
Weidanz,  see  Uhlenhuth  and  Weidanz 


Weigert,  on  aetiology,  11 

Werner,  on  Scharlach  R,  37 

White,  on  atypical  epithelial  growth,  35 ;    on 

the  transmissible  lympho-sarcoma  of  the  dog, 

230 
White   and   Loeb,   on   the   transplantation   of 

stationary  or  receding  tumors,  78 
Whitehead,  on  homoplastic  transplantation,  41 
Whittingham,  see  Walker  and  Whittingham 
WiLKiE,  on  thyroid  adeno-carcinoma  of  the  trout, 

236 
Williams,  on  the  malignancy  of  mouse  tumors, 

i8q 
Wilms,  on  the  production  of  tumors,  25 
WoLFLER,  on  medicine  in  India,  i 
WoGLOM,  on  immunity,  150,  154,  155,  175 
WOLPF,  on  Celsus,  i 
Wyss,  on  X-ray  carcinoma,  33 

Yamanouchi,  on  hypersensibility,  181 

Zacutus,  on  homoplastic  transplantation,  39 
Zahn,  on  the  production  of  tumors,  21 


INDEX    OF   SUBJECTS 


Absorption,  spontaneous,  90;  connective  tissue 
in,  gi,  92,  221,  234;  in  foreign  race,  136; 
giant  cells  in,  gi,  g2 ;  heated  tumor,  83; 
hemorrhage  in,  gi,  g2  ;  histology,  91,  221,  234; 
during  hypersusceptibility,  178;  during  lacta- 
tion, 138;  lymphocytes  in,  92,  177,  221; 
mitosis,  234;  phagocytes,  92,  221;  during 
pregnancy,  138;  re-inoculation  after,  i3g; 
of  spontaneous  tumor,  87,  220,  228,  241,  243; 
of  transplanted  tumor,  83,  87,  90,  120,  122, 
136,  138,  177,  178,  221,  228,  22g,  232,  244,  246 

Absorption  of  graft  in  immunity,  175 

Acquired  resistance,  138,  228,  230,  234,  241,  243, 
24s 

Active  resistance,  138 

Adaptation,  61,  208,  226 

Adrenalin,  gi,  260,  262,  263 

/Etiology,  195;  age,  6,  7,  g,  11,  i2g,  130,  184, 
199,  202,  231,  238;  alien  cells,  23;  anaplasia, 
14,  17;  asexual  phase  of  development,  ig; 
avidity  for  food-stuffs,  7,  ss,  64,  208;  bile, 
I,  2;  cancer  cages,  195;  cancerous  de- 
generation, 12,  14;  conjugation  of  cells,  17; 
embryonal  rests,  8,  9,  10, 11,  13  ;  function,  200  ; 
heredity,  200,  230,  238,  239 ;  heterotypical 
mitosis,  17,  18;  in-breeding,  198;  infection', 
195,  22g,  230,  23s,  237,  238,  239,  241,  242, 
244,  252;  insects,  76,  195,  ig6;  irritation,  in- 
flammation, and  trauma,  4,  5,  6,  7,  8,  10,  11,  13, 
14,  18,  21,  23,  24,  34,  200,  205,  250;  lactation, 
200;  lipoids,  38;  parasites,  igs,  207,  238;  sen- 
sitization and  stimulation,  25;  sex,  igg;  side 
chain  theory,  208;  slumber  cells,  18;  soil,  11; 
stimulus,  s,  II,  13,  17,  18,  25,  34;  trauma,  6, 
8,    250;     twin    pregnancy,    18;     X-rays,    30, 

33 

Age,  in  aetiology,  6,  7,  9,  11,  129,  130,  184,  199, 
202,  231,  238;  limit  of,  in  mouse,  201;  as 
affecting  transplantation,  76,  129,  212,  228, 
24s,  255 ;  of  tumor  and  differentiation,  gg, 
102 ;  of  tumor  and  metastasis,  igo 

AUergie,  172 

Altmann's  granules,  ig3 

Alveolar  carcinoma,  105 

Ameboid  motion  of  cancer  cell,  s,  125 

Amitosis,  sg,  60,  246,  247 

Amyloid  degeneration,  95 

Anaphylaxis,  182 

Anaplasia,  14,  16,  103 

Angioblasts,  chemotaxis  of  cancer  cell  for,  109 

Angioplastic  stroma  reaction,  61 


Aniline  dye  workers,  tumors  of  the  bladder   in, 

33 
Animals,  frequency  of  tumors  among,  183 
Antibodies,  63,  125,  155,  159,  163,  165,  166,  171, 

182,  257,  259,  267 
Appetite  in  tumor-bearing  animals,  94 
Arsenic,  i,  3,  263 
Athrepsia,  159,  208 
Atoxyl,  23s,  263 
Attraxin,  31 
Autoplastic  transplantation,   27,   44,   151,   209, 

212,  223,  24s 
Avidity  for  food-stuffs,   7,   g,   2g,   64,  gg,    161, 

208 

Bed  bugs,  attempted  transmission  by,  76 

Beet,  transplantable  tumor  of,  184 

Betel-nut,  6,  10 

Bile  as  an  aetiological  factor,  i,  2 

Biological  qualities  of  tumor  cells,  al  ;ernations 

in,  75 
Bladder,  tumors  of,  in  aniline  dye  workers,  33 
Blastosis,  38 

Blood  in  tumor-bearing  animals,  96,  2  2g,  234 
Blood  stream,  metastasis  by,  igo,  229,  246 
Body,  growth  during  pregnancy,  g8 

Cachexia,  g2 

Cancer  a  deux  and  cancer  a  trois,  42 

Cancer  cages,  195 

Cancer  cell,  alternations  in  biological  qualities, 

75;  ameboid  motion,  s,  125;  chemotaxis,  61, 

log,  173,  17s;  growth  energy,  83;  resistance 

of,  56,  80,  163,  171,  229,  248,  252,  261 ;  serum 

proof,  163,  170 
Cancer  houses,  42  ;  see  also  "Cancer  cages" 
Cancer,  ovarian,  production  of,  21;    and  twin 
.   births,  18;   zoological  distribution  of,  184 
Carcinoma,    alveolar,   105  ;    sarcomatodes,    80  ; 

X-ray,  s:^ ;   in  the  young,  7 
Cattle,  carcinoma  inner  canthus,  ig7 
Cell  as  a  tissue  unit,  3 
Cell  genesis  and  intercellular  substance,  4 
Chemotaxis,  by  cancer  cell,  61,  log,  173,  175  ;  by 

fat  stains,  31,  32,  33,  35 
Chemotherapy,  263 

Chromosomes,  in  asymmetrical  mitosis,  15 
Classification  of  mouse  tumors,  213 
Clinical  course  of  transplanted  tumors,  g2 ;  of 

spontaneous  tumors,  220 
Collagen,  60 


283 


284 


INDEX    OF    SUBJECTS 


Comparative  growth  rate  of  the  malignant  cell, 
83  _  _ 

Conditions,  of  growth,  129,  130,  147 ;  of  origin, 
129,  130 

Conjugation  of  cells,  17 

Connective  tissue,  growth  energy  of,  6,  7, 
10,  II,  13;  intense  reaction  in  rats,  33;  in 
irradiated  tumors,  261;  mitosis  in,  60;  re- 
moval of  from  tumor  emulsions,  71;  in 
spontaneous  absorption,  91,  92,  221,  234 

Contact  transplantation,  44 

Contagion,  39,  195,  230,  242 

Cow,  hepatic  carcinoma  in,  207 

Cultivation  of  cells  in  vitro,  124,  233 

Cure,  see  "Absorption,  spontaneous,"  and 
"Treatment" 

Cysts,  in  mamma,  205 ;  production  of,  21,  26 

Deciduoma,  production  of,  24 

Degeneration,  amyloid,  95 ;  cancerous,  12, 
14 

Dermoid  cyst,  production  of,  26 

Diet,  amount  in  tumor-bearing  animals,  94 ;  and 
metastasis,  93,  134;  and  recurrence,  134; 
and  susceptibility,  133,  135 ;  and  tumor 
growth,  92 

Differentiation,  age  of  tumor,  99,  s.02 ;  cyclical 
variability  of,  108;  dual,  loi,  104;  in  embryo 
and  tumor,  9 ;  and  growth  energy,  14,  105, 
220;  latent,  104;  lost,  11,  104;  and  meta- 
plasia, 103 ;  in  metastases,  103 ;  in  thyroid 
tumors,  108;  in  transplanted  tissues,  22,  24, 
25  _ 

Distribution,  of  active  resistance,  153  ;  of  mamma 
in  the  mouse,  186 

Dog,  transmissible  lympho-sarcoma,  227 

Dosage,  and  athrepsia,  165,  166,  167,  168,  170; 
and  growth  energy,  65 ;  and  hypersuscepti- 
bility,  180,  181;  and  immunity,  75,  140,  141, 
14s,  146,  149,  150,  151 ;  importance  of  ac- 
curate, 65,  69,  73,  75,  86 ;  small  and  large,  67, 
72,  88 

Dose,  minimal  tumor-forming,  75,  76,  145 

Duration  of  active  resistance,  154 

Dye  workers,  tumors  of  bladder  in,  33 

Early  stages,  see  "Stroma  reaction" 
Edematous  changes  in  the  stroma,  219 
Emaciation  as  a  terminal  event,  92 
Embryo,  growth  energy  of,  84 ;   transplantation 

into,  253 
Embryonal  rests,  8,  9,  10,  11,  13 
Emulsion,  transplantation  by,  68,  71,  165 
Encapsulation,  of  trout  thyroid,  240;  of  tumors, 

192 
Endothelioma,  185,  186,  189,  217,  219 
Epithelioma,  production  of  papillary,  23 
Epithelium,  conjugation  of  leucocytes  with,  17; 

growth  energy  of,  6,  7,  10,   11,  13;    spindle 

shaped,  106 


Equilibrium  between  tissues,  6,  7,  10,  11,  12,  13 
Ereption,  170 

Ferments,  in  metabolism,  98;    treatment  with, 

23s,  263 
Fetal  cells,  immunity  against,    148 ;  immunity 

with,  14s 
Fetus,  nitrogen  value  of,  99;   and  tumor  com- 
pared, 98 
Fibroblasts,  penetration  of  graft  by,  58,  60,  174, 

246 
Fibroplastic  stroma  reaction,  61 
First  appearance  of  active  resistance,  154 
Flies,  attempted  transmission  by,  76 
Fluctuations  in  growth  energy,  67,  85,  220 
Food-stuffs,  avidity  for,   7,  9,  29,  64,  99,  161, 
208;  for  mouse  tumors  in  the  rat,  160;  spe- 
cific, 138,  160,  164;  specific,  in  pregnancy,  138 
Fowl,  transmissible  sarcoma  of,  244 
Fox,  transmission  of  dog  tumor  to,  229,  234,  235 
Frequency  of  tumors  among  animals,  183 
Function,  and  growth  energy,  16 ;  and  aetiology, 
200 

Gametoid  neoplasms,  17 

Gastric  contents,  97 

Generation  stages,  15 

Gestation,  see  "Pregnancy" 

Giant  cells  in  spontaneous  absorption,  91,  92 

Gland,  hibernating,  185 

Graft,  absorption  during  immunity,  175;  and 
soil,  relative  importance  of,  71;  transplanta- 
tion by,  68,  71 ;  vascularization  of,  58,  60,  168, 
174,  246,  247  ;   see  also  "Stroma  reaction  " 

Growth,  of  body  during  pregnancy,  98;  cyto- 
typic  and  organotypic,  9 ;  expansive,  192  ;  in- 
filtrative, 120,  123,  191,  229,  230,  237,  238,  240, 
241,  247;  interval  after  which  it  becomes 
apparent,  77,  83,  225  ;  necessary  for  immunity, 
144,  149;  negative  phase,  67,  135;  of  normal 
tissues  during  pregnancy,  28;  and  origin,  con- 
ditions of,  129,  130;  positive  phase,  67;  pro- 
duction of  atypical  epithehal,  21,  22,  26,  30; 
its  rapidity  in  hypersusceptibihty,  178;  re- 
tarded in  immunity,  145,  146,  147,  172 ; 
rhythms  of,  88 ;  specific  conditions  for,  147 ; 
substance,  64;  of  transplanted  tissues,  20; 
of  tumors  during  pregnancy,  55,  137 ;  of  tumor, 
relation  of  nutrition  to,  92 

Growth  energy,  in  athrepsia,  161,  164,  169,  171 ; 
in  autoplastic  transplantation,  225  ;  and  avid- 
ity, 7,  208;  of  the  cancer  cell,  83;  compara- 
tive in  same  mouse,  225;  decreased,  SS',  and 
differentiation,  14,  105,  220;  and  dosage,  65; 
effect  of  cold  upon,  80;  effect  of  heat  upon, 
80;  effect  of  X-rays  upon,  261;  of  embryo, 
84;  of  embryonic  rests,  8,  9,  10,  11;  of 
epithelium  and  connective  tissue,  6,  7,  10, 
II,  13;  fluctuations  in,  67,  85,  220;  and 
function,    16;    in   grafts  from   stationary   or 


INDEX    OF    SUBJECTS 


28s 


receding  tumors,  78;  and  histology,  105,  220; 
inhibition  of,  68 ;  in  lympho-sarcoma  of  the 
dog,  230;  of  ovum,  17,  84;  in  recurrences,  162, 
164,  209;  in  sarcoma  development,  120,  122, 
123,  124;  of  spontaneous  tumor,  220;  stimu- 
lation of,  68 ;  ill  transmissible  sarcoma  of  the 
fowl,  246;  transplantability  and  virulence,  169 

Hare,  tumors  of,  155,  172 

Health  as  affecting  transplantation,  137,  167 

Hemolysis,  38 

Hemorrhage,  in  irradiated  tumors,  262 ;  in 
spontaneous  absorption,  gi,  92  ;  as  a  terminal 
event,  92 

Hemorrhagic,  changes  in  the  stroma,  219;  tu- 
mours, stroma  of,  109 ;  tumors,  transplantation 
of,  72,  212 

Heredity,  in  aetiology,  200,  230,  238,  239  ;  trans- 
mission of  immunity  and  susceptibility  by, 
55,  157 

Heteroplastic  transplantation,  37,  50,  229,  234, 

235.  25s 

Hibernating  gland,  185 

Histological,  expression  of  growth  energj',  105, 
220;   variations  during  transplantation,  99 

Histology,  and  immunity,  107 ;  of  irradiated 
tumors,  261;  and  malignancy,  104,  107,  217, 
238;  of  mammary  tumors,  186,  213;  of 
receding  tumors,  91,  221,  234;  of  spontaneous 
tumors,  184,  213 ;   and  stroma  reaction,  109 

Historical  review,  i 

Homoplastic  transplantation,  27,  39,  53 

Hormones,  259 

Horn  core,  6  . 

Host  and  tumor,  relation  between,  223 

Hybrids,  susceptibility  and  immunity,  158,  240 
.Hyperemia,  8,  10 

Hypersensibility,  181 

Hypersusceptibility,  178;  and  dosage,  180,  181 ; 
and  immunity,  179,  181;  local,  173;  optimum 
of,  181 ;  produced  by  normal  tissues,  146, 
151,  156,  157,  179,  180,  181;  produced  by 
tumor,  151,  178,  179,  180,  181 ;  rapidity  of 
growth  in,  178;  specificity  of,  180;  spon- 
taneous absorption  in,  178 ;  and  time  interval, 
178,  180,  181 

Hypertrophy,  nodular,  205  ;  of  organs  in  tumor- 
bearing  animals,  93 

Immune  zone,  230 

Immunity,  128;  abrogation  by  operation,  162; 
absorption  of  graft  in,  175  ;  acquired,  138,  228, 
230,  234,  241,  243,  24s;  active,  138;  and 
age,  76,  129,  228,  245,  255;  and  allergic,  172; 
athreptic,  159,  208;  with  autologous  tissue, 
150;  with  autolyzed  tissue,  137,  149,  150;  to 
autoplastic  transplantation,  151 ;  and  chemo- 
taxis,  173,  175;  common  and  specific,  142; 
concomitant,  67,  70,  74,  87,  162,  165,  167;  de- 
velopment of  spontaneous  tumors  during,  128 ; 


distribution  of,  153;  and  dosage,  75,  140,  141, 
14s,  146,  149,  150,  151;  duration  of,  154; 
against  fetal  cells,  148;  with  fetal  cells,  145; 
first  appearance  of,  154;  growth  necessary 
for,  144,  149;  growth  retarded  m,  145,  146, 
147,  172;  as  affected  by  health,  137,  167; 
hereditary  transmission  of,  55,  157;  and  his- 
tology, 107;  in  hybrids,  158,  240;  and 
hypersusceptibility,  179,  181 ;  with  intact 
homologous  normal  cells,  148;  with  intact 
homologous  tumor  cells,  143 ;  leucocyte  in, 
236;  lymphocyte  in,  176,  234,  247,  248: 
lymphoid  cells  in,  173;  macrophage  reaction 
in,  173;  mitosis  in,  174;  natural,  128,  228, 
229,  241,  247;  nature  of,  159;  with  normal 
tissue,  144;  and  operation,  162;  and  para- 
biosis, 258;  survival  of  parenchyma  in,  174, 
17s;  partial,  107,  172;  passive,  155;  plasma 
cell  in,  173,  177;  and  pregnancy,  137;  pre- 
metastatic  stage  of,  152,  230;   and  race,  55, 

76,  79,  130,  231,  245,  255  ;  resistance  of  timior 
cell  to,  163  ;  and  selection,  141  ;  and  sex,  137  ; 
specificity  of,  122,  141,  147;  stroma  reaction 
in,  168,  174,  247;  with  tumor,  122,  138;  in 
tumor-bearing  animals,  150,  152,  161;  tumor 
mixtures  in,  133;  X-stuff  in,  160 

In-breeding,  198 

Incitant,  specific,  160 

IndividuaHty,  212,  225 

Infection,  in  astiology,  195,  229,  230,  235,  237, 

238,   239,   241,   242,   244,   252;  as  a  terminal 

event,  92;    or  transplantation?   58,  229,  230, 

231,  232,  234 
Infectiveness,  variations  in,  89 
Infectivity,  195 
Infiltrative  growth,  120,  123,  191,  229,  230,  237, 

238,  240,  241,  247 
Inflammation,  in  etiology,  7,  8,  10,  13,  24,  205; 

chronic,  of  mamma,  205 
Inheritance,  Mendelian,  and  susceptibility,  158 
Inoculation,  site,  76 ;   of  stationary  or  receding 

tumors,  78 ;    of  tumor  mixtures,  79  ;    see  also 

"  Transplantation  " 
Insects  in  aetiology,  76,  195,  196 
Intercellular  substance  and  cell  genesis,  4 
Interval  after  which  growth  becomes  apparent, 

77,  83,  225 

Intervals  between  successive  inoculations,  71 

Inunction,  transplantation  by,  75 

Iodine,  242,  243 

Irritation  in  aetiology,  4,  5,  6,  7,  10,  18,  21,  23 

Kangri  basket,  6,  10 
Karyokinesis,   see  "  Mitosis  " 
Kataplasia,  16 
Keloid,  production  of,  29 
Keratin,  83,  100,  107 

Lactation,   as  an    aetiological  factor,    200;    re- 
gression of  tumors  during,  138 


286 


INDEX    OF    SUBJECTS 


Latent  period,  effect  of  heat  upon,  83 
Leeches,  attempted  transmission  by,  76 
Leucocyte,  conjugation  with  epithelium,  17;  in 

immunity,  236 
Lipoids,  significance  of,  38,  266 
Lymph  nodes,  enlargement  recognized  by  Celsus, 

2 
Lymphocyte,  in  immunity,  176,  234,  247,  248;  in 

spontaneous  absorption,  92,  177,  221 
Lymphoid  cells  in  immunity,  173 
Lympho-sarcoma  of  the  dog,  227 
Lymph  stream,  metastasis  by,  53,  57,  190,  192, 

227,  229,  246 

Macrophage  reaction  in  immunity,  173 

Malignancy,  189;  and  histology,  104,  107,  217, 
238;  and  metastasis,  161;  and  mitosis,  215, 
218;   of  mouse  tumors,  189 

Malignin,  260 

Mamma,  chronic  inflammation  of,  205 ;  cyst 
formation  in,  205  ;  distribution  in  the  mouse, 
186;  histology  of  tumors,  186,  213;  nodular 
hypertrophy  of,  205 ;  normal,  205 ;  in  old 
mice,  207 ;  origin  of  tumors  in,  184,  193,  200; 
sclerosis  of,  205 

Marrow  in  tumor-bearing  animals,  96 

Membrane  in  relation  to  therapeutics,  267 

Mendelian  inheritance  and  susceptibility,  158 

Mercury,  243 

Metabolism  in  tumor-bearing  animals,  97 

Metaplasia  and  differentiation,  103 

Metastases,  transplantation  of,  79 

Metastasis,  189;  age  of  tumor,  190;  and  athrep- 
sia,  161;  by  blood  stream,  190,  229,  246;  and 
diet,  93, 134 ;  differentiation  in,  103  ;  in  the  dog, 
227,  228,  229,  230;  early  stages  in,  114,  250; 
in  the  eyelid,  244 ;  in  the  fowl,  244,  246,  250 ; 
in  the  heart,  244,  246  ;  immunity  against,  134, 
151 ;  in  the  intestinal  wall,  244 ;  in  the  kidney, 
190,  244;  in  the  liver,  igo,  191,  244,  246;  in 
the  lungs,  92,  114,  i8g,  192,  222,  244;  by 
lymph  stream,  53,  57,  190,  192,  227,  229,  246; 
and  malignancy,  161 ;  in  the  mediastinum, 
190;  metastatic  stage,  152,  230;  mode  of 
origin,  4,  5,  114,  250;  in  the  ovary,  190;  on 
the  peritoneimi,  190;  premetastatic  stage, 
152,  230 ;  prevention  of,  93,  134, 151,  258 ;  ret- 
rograde, 44;  in  the  retroperitoneal  tissue,  190  ; 
in  sarcoma  development,  112,  114,  120,  123; 
in  the  skin,  244;  in  the  spleen,  190,  227,  246; 
in  spontaneous  tumors,  53,  57,  189,  192,  193, 
226;  stroma  reaction  in,  114,  250;  in  trans- 
plantable tumors,  190,  192  ;  in  the  trout,  238, 
239,  240,  241,  242 

Metastatic  stage,  152,  230 

Mincing  machine,  69 

Mitosis,  asymmetrical,  15,  68;  in  connective  tis- 
sue surrounding  graft,  60;  in  young  grafts, 
60,  174,  233,  247;  in  the  fowl,  247;  hetero- 
typical,  17,  18;  hyperchromatic,  14,  217;  hy- 


pochromatic,  14;  in  immunity,  174;  and  ma- 
lignancy, 215,  2i8;  in  spontaneous  absorption, 
234;  stimulation  of,  26;  in  vitro,  125,  126,  233 

Mixed  tumors,  109;  purification  of,  82,  117,  120; 
see  also  "Tumor  mixtures"  and  "Sarcoma 
development" 

Mixtures,  see  "Tumor  mixtures  " 

Morphology,  see  "Histology  " 

Mouse,  age  limit  in,  201 ;  distribution  of  mamma 
in,  186;  tumors  of,  184;  carcinoma,  growth 
of,  in  rat,  159 

Multiple,  spontaneous  tumors,  188,  199,  200; 
transplantation,  72 ;  transplanted  tumors,  72, 
150,  152,  161,  208 

Natural  resistance,  128,  228,  229,  241,  247 

Nature  of  the  resistant  state,  159 

Needle  for  inoculation,  70  (footnote) 

Nipple,  retraction  of,  2 

Nitrogen  balance,  98 

Nitrogen  value  of  fetus,  99 

Normal  tissues,  growth  of,  21  ;  growth  during 
pregnancy,  28 ;  hypersusceptibility  produced 
by,  146,  151,  156,  157,  179,  180,  181;  resist- 
ance produced  by,  144 

Nucleus,  discovery  of,  3 

Nutriceptors,  64,  208 

Nutrition  and  tumor  growth,  92 

Nutritive  capacity,  limit  of,  167 

Operation,  and  immunity.  162;  recurrence  after, 
189,  192,  222,  229;  re-inoculation  after,  161; 
results  of,  221 ;  transplantation  during,  47,  226 

Organs,  transplantation  into,  77,  154;  hyper- 
trophy of,  in  tumor-bearing  animals,  93   . 

Origin,  conditions  of,  1 29, 130 ;  of  metastases,  4,  s, 
114,  250;  multicentric,  205,  217;  site  of,  184, 
193,  200 

Osteo-chondro-sarcoma,  transplantable,  100 

Ovum,  growth  energy  of,  17,  84 

Pan-immunity,  141 

Papilloma,  production  of,  23 

Parabiosis,  258 

Parasites  in  setiology,  19s,  207 

Parenchyma,  histological  variations  during  trans- 
plantation, 99  ;  secondary  changes  in,  215; 
survival  in  immune  animals,  174,  17s;  sur- 
vival after  transplantation,  58,  59,  168,  174; 
variations  during  transplantation,  99 

Partial  immunity,  107,  172 

Passage,  rapid,  71 

Passive  immunity,  155 

Phagocytes,  in  spontaneous  absorption,  92,  221 ; 
in  vitro,  125 

Pin  prick,  transplantation  by,  76 

Plasma  cell  in  immunity,  173,  177 

Pluri-immunity,  142 

Pregnancy,  and  athrepsia,  172;  growth  of  body 
during,  98;    growth  of  normal  tissues  during. 


INDEX    or    SUBJECTS 


287 


28;  growth  of  tumors  during,  55,  137;  as 
affecting  transplantation,  137  ;  specific  food- 
stuffs in,  1 38;  spontaneous  absorption  during, 
138;  weight  of  organs  during,  93,  94 

Premetastatic  stage,  152,  230 

Prevention,  of  metastasis,  93,  134,  151,  258; 
of  recurrence,  i,  134,  151,  164,  192 

Proliferative  energy,  169 ;  see  also  "  Growth 
energy" 

Purification  of  mixed  tumors,  82,  117,  120 

Pabbit,  uterine  carcinoma  in,  22 

Kace  as  affecting  transplantation,  55,  76,  79,  130, 
231,  24s,  25s 

Radium,  83,  91,  149,  181,  261 

Rat,  food-stuffs  for  mouse  tumors  in,  160 ;  growth 
of  mouse  carcinoma  in,  159  ;  intense  connective 
tissue  reaction  in,  :is  ;  tumors  of,  1S8 

Receptors,  64,  171,  208 

Recession,  see  "Absorption,  spontaneous,"  and 
"Treatment" 

Recovery,  see  "Absorption,  spontaneous"  and 
"Treatment" 

Recurrence,  and  diet,  134 ;  growth  energ>'  in,  162, 
164,  209;  prevention  of,  i,  134,  151,  164,  192; 
after  operation,  189,  192,  222,  229;  in  relation 
to  re-inoculation,  164;  after  sarcoma  develop- 
ment, 113,  123  ;  increase  in  weight  during,  222 

Refractory  condition,  see  "Immunity" 

Regression,  see  "Absorption,  spontaneous"  and 
"Treatment" 

Reinoculation,  after  operation,  161 ;  in  relation 
to  recurrence,  164;  after  spontaneous  ab- 
sorption, 139;  of  tumor-bearing  animads,  150, 
152, 161,  164, 166,  167,  168,  212,  223,  230,  232; 
and  vdrulence,  140,  143,  171 

Relation  between  tumor  and  host,  223 

Resistance,  128  ;  see  also  "Immunity" 

Resistance  of  cancer  cell,  56,  80,  163,  171,  229, 
248,  252,  261 

Retraction  of  nipple,  2 

Retrograde  metastasis,  44 

Rhythms  of  growth,  88 

Salvarsan,  235 

Sarcoma,  development,  79,  106,  109;  production 
of,  23,  30;  stroma  reaction  in,  59, 116  ;  X-ray,  30 

Scharlach  R,  27,  30 

Sclerosis  of  mamma,  205 

Selection  and  immunity,  141 

Selenium,  263 

Senility,  see  "Age" 

Sensitization,  25 

Serum-proof  cancer  cells,  163,  170 

Sex,  in  etiology,  199;  as  affecting  transplanta- 
tion, 137 

Side  chain  theory  in  jetiology,  208 

Size  attained  by  tumors,  57,  62,  192 

Slumber  cell  hypothesis,  18 

Soil,  in  setiologA',   11;    and    graft,  relative  im- 


portance of,  71;  and  sarcoma  development, 
no,  116 

Spontaneous,  absorption,  90;   tumors,  183 

Stimulation,  of  growth  power,  68;  of  mitosis,  26 

Stimulus  in  aetiologj',  5,  11,  13,  17,  18,  25,  34 

Stroma,  death  following  transplantation,  58,  59, 
168,  174;  edematous  changes  in,  219;  hem- 
orrhagic changes  in,  219;  in  hemorrhagic 
tumors,  109 ;  histological  changes  during 
transplantation,  log ;  relation  to  sarcoma 
development,  in;  sarcoma  development  in, 
109  ;   secondary  changes  in,  215 

Stroma  reaction,  58 ;  amitosis  in,  60,  246,  247 ; 
angioplastic  and  fibroplastic,  61 ;  in  athrepsia, 
168;  in  the  dog,  229,  231,  232,  234;  in  the 
fowl,  246 ;  and  histological  structure,  109 ;  in 
immunity,  16S,  174,  247;  in  metastases,  114, 
250;  mitosis  in,  60,  174,  233,  247;  in  the 
mouse,  58,  168,  174,  176;  in  the  rat,  59, 
175;   in  sarcoma,   59,   116;   specificity  of,  60 

Structure  of  origin  in  the  mouse,  184  193,  200 

Structure,  see  "Histology" 

Sudan  III,  30 

Summarj',  270 

Susceptibility,  and  age,  76,  129,  212,  228,  245, 
255  ;  and  diet,  133,  135 ;  and  health,  137,  167  ; 
hereditary'  transmission  of,  55, 157;  of  hybrids, 
158,  240;  increased,  165,  166,  168,  178,  223; 
and  pregnancy,  137 ;  and  race,  55,  76,  79,  130, 
231,  24s,  255;  and  sex,  137;  in  tumor-bear- 
ing animals,  165,  166,  168,  223;  for  txmior 
mixtures,  79,  133 

S^'ringe  for  inoculation,  69 

Technic  of  inoculation,  68 

Tellurium,  263 

Teratoma,  production  of,  25,  26 

Therapeutics,  see  "Absorption,  spontaneous," 
and  "Treatment" 

Thyroid,  adeno-carcinoma  of  the  trout,  236; 
gland,  non-encapsulation  in  the  trout,  240 

Toxins,  in  treatment,   235 ;    in  metaboUsm,  98 

Transfer,  of  tumors  from  one  person  to  another, 
39 ;    of  human  tumors  to  animals,  50 

Transmissibility,  earher  observations  on,  39 

Transmissible  sarcoma  of  the  fowl,  244 

Transplantabihty,  62 ;  diminished,  78  (see  also 
"  Resistance  of  cancer  cell  ")  ;  growth  energy, 
and  \arulence,  169;  of  thyroid  adeno-carcinoma 
of  the  trout,  240,  242 

Transplantation,  as  affected  by  age,  76,  129, 
212,  228,  24s,  255;  autoplastic,  27,  44, 
151,  209,  212,  223,  245;  and  avidity,  208; 
into  bearer,  44  ;  behaNdor  of  tumor  cell  during, 
loi ;  by  contact,  44;  by  contagion,  39,  195, 
230,  242 ;  into  embryo,  253 ;  emulsion  and 
graft  methods,  68,  71 ;  first  appearance  of 
tumor  after,  77,  S3,  225  ;  as  affected  by  health, 
I37>  167;  of  hemorrhagic  tumors,  72,  212; 
heteroplastic,  37,  50,  229,  234,  235,  255;  his- 


INDEX    OF    SUBJECTS 


tological  variations  during,  99;  homoplastic, 
27,  39,  53;  or  infection?  58,  229,  230, 
231,  232,  234;  of  injured  cells,  80  (see  also 
"Resistance  of  cancer  cell") ;  through  insects, 
etc.,  76,  195,  196;  by  inunction,  75;  of  me- 
tastases, 79;  multiple,  72;  needle  for,  70 
(footnote);  during  operation,  47,  226; 
optimum  conditions  for,  70,  88;  into  organs, 
77,  154;  sur\'ival  of  parenchyma  after,  58,  59, 
168,  174;  by  pin  prick,  76;  as  affected  by 
pregnancy,  137 ;  as  affected  by  race,  55,  76, 
79,  130,  231,  245,  255  ;  as  affected  by  sex,  137  ; 
site  of  election  for,  76 ;  within  the  same  species, 
27,  39,  S3 ;  of  spontaneous  tumors,  65,  71,  72, 
75,  212,  223,  226;  of  stationary  or  receding  tu- 
mors, 78,  225  ;  death  of  stroma  after,  58,  59, 
168,  174;  increased  susceptibihty  to,  165,  166, 
168,  178,  223;  syringe  for,  69;  technic  of ,  68; 
as  affected  by  trauma,  249,  251 ;  into  tumor- 
bearing  animals,  150,  152,  161,  164,  166,  167, 
168,  212,  223,  230,  232;  of  tmnor  mixtures, 
79;  of  warts,  44;  zigzag,  159 
Transplantations,  inter\^als  between  successive, 

71 

Transplanted  tissues,  differentiation  in,  22,  24, 
25   growth  of,  20;  growth  diudng  pregnancj',  28 

Transplanted  tumors,  58 

Trauma,  in  relation  to  aetiology,  6,  8,  250;  in 
relation  to  transplantation,  249,  251 

Treatment,  i,  2,  3,  19,  230,  235,  236,  256 

Trout,  th>Toid  adeno-carcinoma  in,  236;  non- 
encapsulation  of  thjToid  gland,  240 

Tumor,  hrst  appearance  after  transplantation, 
77,  83,  225;  cHnical  course  of,  92,  220;  and 
fetus  compared,  98 ;  and  host,  relation  be- 
tween, 223  ;  hypersusceptibihty  produced  by, 
151,  178,  179,  180,  181;  immunity  produced 
by,  122,  138;  mixtures  and  athrepsia,  171; 
mixtures,  susceptibility  and  immunity  for,  79, 
133;  mixtures,  transplantation  of,  79;  reced- 
ing, transplantation  of,  78;  size  attained  by, 
57,  62,  192 ;  the  spontaneous,  183 ;  sponta- 
neous, development  during  immunity,  128; 
spontaneous,  distinguished  from  transplant- 
able, 97,  212;  spontaneous,  fluctuations  in 
growth  energ>',  87 ;  spontaneous,  frequency 
of  occurrence,  183,  199;  spontaneous,  growth 
energy,  220;  spontaneous,  histology,  184,  213 ; 


spontaneous,  metastasis,  53,  57,  189,  192,  193, 
226;  spontaneous,  multiple,  188,  199,  200; 
spwntaneous,  recurrence,  189,  222 ;  spontane- 
ous, sarcoma  development  in,  113;  sponta- 
neous, spontaneous  absorption  of,  87,  220,  228, 
241,  243;  spontaneous,  temporary  arrest,  220; 
spontaneous,  transplantation  of,  65,  71,  72, 
75,  212,  223,226;  stationarj^  transplantation 
of,  78,  225  ;  transplantable,  distinguished  from 
spontaneous,  97,  212  ;  transplantable,  metas- 
tasis, 190,  192 ;  transplantable,  spontaneous 
absorption  of,  83,  87,  90,  120,  122,  136,  138, 
177,  178,  221,  228,  229,  232,  244,  246;  the 
transplanted,  58 ;  zone,  230 

Tumors,  attempts  to  produce,  20;  of  the  dog, 
227;  of  the  fowl,  244;  of  a  nature  still  un- 
decided, 227;  of  bladder  in  aniline  dye 
workers,  33 ;  growth  energy  in  stationarj'  or  re- 
ceding, 78;  of  the  hare,  155,  172;  mixed,  109; 
of  the  mouse,  184 ;  origin  of  mammary,  184, 
193,  200;  of  the  rabbit,  22;  of  the  rat,  188; 
transplantable,  multiple,  72,  150,  152,  161, 
208 ;  of  the  trout,  236 

Twin  births  in  relation  to  cancer,  18 

Variations,  in  infectiveness,  89 ;  in  parenchyma 

during  transplantation,  99 
Vascularization  of  graft,  58,  60, 168,  174,  246,  247 
Virulence,  and  adaptation,  61 ;  and  athrepsia, 
161,  164,  165,  166,  167,  169,  170,  171;  in- 
creased, 79,  210;  maximal,  170;  and  re- 
inoculation,  140,  141,  143,  171 ;  and  sarcoma 
development,  112,  117,  118,  120,  124;  trans- 
plantability,  and  growth  energy,  169 

Warts,  transplantation  of,  44 

Weight,    increase    during    recurrence,    222;    of 

organs  in  tumor-bearing  animals,  93  ;  of  timior- 

bearing  animals,  94,  97,  221,  222 

X-ray,  carcinoma,  33  ;   sarcoma,  30 
X-rays,  30,  35,  260,  261 
X-stuff,  160 

Yoimg,  carcinoma  in  the,  7 

Zigzag  inoculation,  159 

Zoological  distribution  of  cancer,  184 


RC26i 

Woglom  1913 

•  ••  The  study  of  experinien-  c.l 
tal  cancer. 


